You can do each of those at various hosts and own nothing. Or own a couple "over priced" cards and do it all at home on battery power for a few hours while the power is out.
Your comment is like a meta comment of "LLMs are generating everything, after a while the ouroboros will eat itself. (Which I agree with)" If people aren't hacking on this shit just because, you have completely conceded control of software to a handful of sociopaths, and open source software is dead.
From a quick search a 3090 looks to go for about 1500-2000 USD. So let's say $4K for two.
I'm spending far over $1K/month (employer-paid) on cloud AI, so if that could be anywhere near comparable we're only looking at less than a few months break-even.
Less really, because some months are more expensive. This month I'm up to ~$500 and it is only day 4 of this month.
You could sell those and have enough money to pay for hosted inference for years.