For any higher level position I disagree, the specificity is logical:
These days you are hiring into a position the person is probably stuck in for the duration of the 3-5 years they are going to be at your company and you are going to be paying the rate that is their current salary plus whatever increases they didn't get at their last gig.
You can hire someone that works in the toolchain you work in, save on costs because their time getting up to speed is lower, and they are more likely to write something your existing developers are going to follow, or you can hire someone with a solid background, spend time teaching them, and lose time when your other developers encounter their early attempts which look like their last framework's top ideas ported crudely to the toolchain you use.
You get to keep the person about the same time either way, but the second situation gives you less return on investment, and there are plenty of candidates to choose from so why not make the selection that gives you more results for similar expense?
On top of that, some of the concepts, while possible to implement in various languages are very much the wrong way to do something in certain languages for low level technical reasons. It started with the C vs C++ crowds, spread into the various flavors then outward into new languages as they developed with the various compilers/runtimes being built with different assumptions.
I know what a binary tree, hash table, linked list and event handler look like in many languages, I have implemented them in many, but I also have many years of experience on when to avoid them like the plague in my chosen language and enough sense to know that even if I learned a new language to the point I was fluent in it I couldn't legitimately demand the same pay as I can in the language I have more than a decade of experience in.
What I do see is in the lower tier of dev jobs they are posted the same way as the more senior jobs. This I agree is a probably a bit unnecessary as almost all Jr candidates are useless right off of school, but the market isn't tight enough to post even Jr positions as no experience needed, and if you are going to ask for experience you might as well ask for related experience as those candidates are out there.
The other factor at play in the REALLY specific job postings is large organization politics, or god forbid: unions. If a manager's grade is determined by the number of staff they manage keeping an open position open lets the manager keep their position and meet budget sometimes. Other times having a position that cannot be filled provides the justification to bring the rest of the department's rate up to market levels.
Companies with union dictated hiring rules are the only companies I have ever observed actually "unable" to fill a position due to the checklists, and even that isn't that common, but we did have a couple local employers that would post things like Level X platform Y developer with Z years experience where Z was 3x the number of years Y had existed. I applied for some of those initially our of school assuming it was a mistake only to find our from the hiring manager that all employees at level X require Z years of experience since their last collective bargaining with the mechanical and electrical unions. I had no relationship with the union so I could only respond that I had worked in that platform since z/3 years ago when it was initially released and the hiring manager apologized for wasting everyone's time.
That position remained posted until the company closed all of the local locations and reopened several states away with no union the year before Z years would have actually been possible.
I am sure there are people playing games with it for H1B purposes as well, but at least in the geographic area I work in, most companies that were going to try that route already did, many learned their lessons and are already pulling back from it. From what I have seen, the level of fraud in the overseas universities and technical schools is going to solve the H1B problem faster than legislation will everywhere except for possibly the west coast.
For any higher level position I disagree, the specificity is logical:
These days you are hiring into a position the person is probably stuck in for the duration of the 3-5 years they are going to be at your company and you are going to be paying the rate that is their current salary plus whatever increases they didn't get at their last gig.
You can hire someone that works in the toolchain you work in, save on costs because their time getting up to speed is lower, and they are more likely to write something your existing developers are going to follow, or you can hire someone with a solid background, spend time teaching them, and lose time when your other developers encounter their early attempts which look like their last framework's top ideas ported crudely to the toolchain you use.
You get to keep the person about the same time either way, but the second situation gives you less return on investment, and there are plenty of candidates to choose from so why not make the selection that gives you more results for similar expense?
On top of that, some of the concepts, while possible to implement in various languages are very much the wrong way to do something in certain languages for low level technical reasons. It started with the C vs C++ crowds, spread into the various flavors then outward into new languages as they developed with the various compilers/runtimes being built with different assumptions.
I know what a binary tree, hash table, linked list and event handler look like in many languages, I have implemented them in many, but I also have many years of experience on when to avoid them like the plague in my chosen language and enough sense to know that even if I learned a new language to the point I was fluent in it I couldn't legitimately demand the same pay as I can in the language I have more than a decade of experience in.
What I do see is in the lower tier of dev jobs they are posted the same way as the more senior jobs. This I agree is a probably a bit unnecessary as almost all Jr candidates are useless right off of school, but the market isn't tight enough to post even Jr positions as no experience needed, and if you are going to ask for experience you might as well ask for related experience as those candidates are out there.
The other factor at play in the REALLY specific job postings is large organization politics, or god forbid: unions. If a manager's grade is determined by the number of staff they manage keeping an open position open lets the manager keep their position and meet budget sometimes. Other times having a position that cannot be filled provides the justification to bring the rest of the department's rate up to market levels.
Companies with union dictated hiring rules are the only companies I have ever observed actually "unable" to fill a position due to the checklists, and even that isn't that common, but we did have a couple local employers that would post things like Level X platform Y developer with Z years experience where Z was 3x the number of years Y had existed. I applied for some of those initially our of school assuming it was a mistake only to find our from the hiring manager that all employees at level X require Z years of experience since their last collective bargaining with the mechanical and electrical unions. I had no relationship with the union so I could only respond that I had worked in that platform since z/3 years ago when it was initially released and the hiring manager apologized for wasting everyone's time.
That position remained posted until the company closed all of the local locations and reopened several states away with no union the year before Z years would have actually been possible.
I am sure there are people playing games with it for H1B purposes as well, but at least in the geographic area I work in, most companies that were going to try that route already did, many learned their lessons and are already pulling back from it. From what I have seen, the level of fraud in the overseas universities and technical schools is going to solve the H1B problem faster than legislation will everywhere except for possibly the west coast.