The tipping point will be when an AI/LLM is as good as a human with a bachelor's degree. At that point, it won't matter how legitimate the credentials are, because the jobs just won't be there for people anymore.
For software at least, that point was probably reached like 10 months ago, and has definitely been blown past by now. It's not like humans with a fresh degree and no experience have much business/product sense, which is the only place where the AI might still be lacking. From what I can see, usually "senior" (so generally several years experience) means "can be asked to do a vague thing and they'll actually get it done independently."
For a lot of office jobs, in terms of what people do on computers, this is already the case. However, I don't think a lot of these jobs are going away just yet.