Okay, first of all, if someone physically can't do a job, obviously they shouldn't be in the job. But DEI isn't doing that. That's the main reason why Trump saying the crash was because of DEI was blatantly false, for example. You literally can't fly unless you meet a health standard, and to become a pilot or a flight control operator is is extremely difficult as it is. They aren't shoving someone who physically can't do that job into that job.
Also, you may see the LGBTQ that way, but many hirers don't, that's the whole reason it's a thing, because many wouldn't hire them despite the fact they are qualified because they're queer. You can meet all the standards out there, but if the hirer is a bigot, you won't get hired.
Yes, it is creating an incentive to hire diverse people, but there is always the assumption that the person who is being hired ISN'T also qualified. It's a strawman argument to say that someone who was hired because of DEI was put above someone who is more qualified. There are so many more factors that go into that. They aren't hiring bumbling bafoons because tey are a minority while not hiring an ultra genius, that just doesn't happen.
Teachers are hired for their ability to teach primarily. Going purely off physical ability in that situation is ignoring that the minority being hired could be better at the thing their job surrounds, to teach. That's a strawman that ignores the other numerous details and factors that go into that.