It's really beyond my comprehension. To think there are talented people out there doing godly miracle work. And then you get shitty emulators from actual companies e.g. the PS2 emulator comes to my mind, yes its as basic as it gets. Then there's RPCS3, holy shit, this thing is absolutely bonkers, we could have PS3 games now, but companies are just braindead. Why not just hire these people? It's a win win for everyone.
I'd guess the answer is that these companies are still organizations filled with people who have different priorities and career ambitions and workplace interplay. They are not a monolith.
You don't want to be the guy who fires half of his department who have the on-paper qualifications and backgrounds, just to gamble and hire people who may or may not have the full prerequisites, all for the sake of one (maybe) 2-year project because they *might* be able to get it done to a slightly higher standard if they even fit into the workplace structure at all.
This assumes the one department head is even the one able to make that decision on his own. Most of the time, if you want to overhaul your department, you might need to convince higherups, draft presentations, carry out adverstising/interviews/hiring/payroll increases when hiring new (more qualified) staff. It's all bureaucratic.
This also assumes the higherups even care about delivering a slightly better product at higher cost when the minimum viable product is "fine enough".
These are just my assumptions, of course