Earlier quoted context omitted.
"Surely my genAI product won't be used to spam zero-effort slop all over the internet!" - guy whose genAI product will definitely be used to spam zero-effort slop all over the internet.
I think their main target is corporate creative jobs. Background music to ads/videos/etc. And just like with all AI, they will eat the jobs that support the rest of the system, making it a one and done. It will give a one time boost, and then be stuck at that level because creatives won't have the jobs that allowed them to add to the domain. In this case new music styles. New techniques. It's literally eating the see…
As people get fed up with AI generated crap, companies will start to pay very good money to the few remaining good human creatives in order to differentiate themselves. The field will then be seen as desirable, people will start working hard for to get these jobs, companies will take apprentices hoping they will become masters later, etc... We may lose a generation, but certainly not the entire future.
Of course, it is just one of many possible futures, but I think the most likely if you take your assumptions as a postulate. It may turn out that AIs end up not displacing creative jobs too much, or going the other way, that AIs end up being truly creative, building their own culture together with humans, or not.