This might not be insightful from your perspective, because you've thought about it before, but it needs to be said. Just like a NO DIVING sign in the shallow end, most people already know, but some people who don't know might not know if it isn't stated.
I don't see, why ChatGPT changed that, I only tried it a little bit so far, but it doesn't usually give you a ready program, right? It gives you snippets, that might work, or not, but in my case required understanding of the domain. So I could adopt the scripts to my need, but I doubt a beginner could. At least not for anything non trivial. Also those beginners can ask a million stupid questions to the AI that just patiently answers. So yes, those answers can be wrong, but that can happen in a forum as well and even in university occasionally I was taught some BS.
So yes, ChatGPT changes the game a bit, but not that drastic. If you want to become a professional programmer, you still have to get your hands dirty and grind away the basics. But you cannot skip certain things, or you never manage to get even a mid sized project running performant and stable.
And if necessary, it would be probably trivial to weed out "programmers" that aren't really programmers by asking them some questions directly.
I agree with your assertion that non-trivial things will weed out "programmers", I just think that ChatGPT will get people further and that definition of "non-trivial" will shift a bit - possibly far enough people will have an easier time leaking their API keys through Frankenstein apps they post online.