Even if there were a few points on the stones you could go "that's logical, sensible"... the whole thing gets overshadowed and rightfully so by "maintaining human population under 500,000,000..."
Now how exactly do you do that?
I remember reading some rather elaborated (and very science based) stuff saying that Earth would easily be able to support a self sustainable life/future for vastly more than that, IIRC it's been something around those 8 billion humans we are right now.
Very obviously, that however would demand a more or less drastic change in the way ressources are used and how "wealth" is distributed. The most interesting takeaway however being that the authors said that it'd be possible with capitalism still in place (because they seemed to agree that us humans can't completely avoid capitalism), but it'd take a "modified" version of capitalism, let's call it "sustainable capitalism" (for lack of better words).
Anyhow, whatever the number might be, it's absolutely obvious that Earth can't deal with endless people, so there's a certain limit. But it's still completely stupid to come up with any arbitrary figures (such as those 500,000,000), because if we were taking these as our guideline, it needed drastic measures to get there. Some of them very certainly being pretty anti-human.
Personally, I think that population growth would perfectly regulate itself anyway, in case all/most people were fine with their lives, so it'd very likely become a non-issue.
And whatever the final goal might be, there's no way around us having to start with the situation as is. There's no sense in wild speculations about whatever all-humans-are-happy utopias, in the end they may look completely different anyway.
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Whatever, to get back to topic: AI (along with "robot-ation") so far isn't exactly serving much of the once (and still) promised glory for humans.
The situation regarding AI music pretty much shows that under a lens. Suno has about zero purposes others than making quick money. During the last decades there's never been any shortage of fantastic music of any genre or use case. In fact, the very opposite is true. Even pre-Suno, it's been an overwhelming amount of music to listen to.
There's been no shortage of composers, players, audio engineers, producers and whatsoever.
Oh, sure, there's "but I can't sing so I'm happy about Suno singing for me". But again, that just comes down to laziness and money. There's Fiverr with kickass singers galore if you want to work remotely.
"But that singer doesn't do it as good as Suno!" - so, a) either ask someone else or b) try to get the best out of what you have. These things are part of the very essence of music - not perfection.
And so far it's the very same with each environment that AI is breaking into at this very moment.
It doesn't serve anyone if kids can do their homework via Chat GPT - sure, it's a short time "remedy", but it's still worth noting in the long run.
Being able to create silly videos might be fun for a while - but we're already drowning in them (take a look at TikTok, Instagram and YT) and others than some quick laughs and maybe some quick money for the more successful "creators" there's nothing to be had from them.
Etc.
I said so before: An AI actually serving humans needed to care about humanity's biggest issues (not gonna list them here because that'd take this too much into politics). Taking over jobs, destroying pretty much the entire more or less creative/art scene and what not - none of that has ever been something we needed.
I don't think we will be able to get there, though. For reasons that we can't discuss about here.