My kids (and I) certainly don't see it as exploitation - they love learning to create games, and would be happy to do it even without any chance of payout.
I don't think the $1k minimum payout is crazy either, as the overhead of paying 10s of thousands of kids $11.32 would kill margins (leading to Robux having to take a higher %age). I'd have to think most kids are in the same boat as mine - if their games ever earn them any Robux, they'll turn around and spend those Robux in another game, because that's what they want to do with it anyway.
Same with me. My kid makes Roblox games for her and her friends. It didn't take her long to realize that the odds of her making any money at all were very slim. In the meantime she gets to learn programming skills in a way that she finds fun.
I do feel a bit bad for the older kids that put real effort into it, but I don't see how it's much worse than trying to start a youtube or twitch channel and failing. At least with coding they're getting some valuable experience.
All that said, the way they sell "Robux" is absolutely predatory. We've had to have several talks about what is reasonable to spend money on. They even let you pay with Amazon. Payments via Amazon are on by default for Amazon accounts and don't require re-authentication, so a kid who clicks on a link in Roblox on a computer that has already authenticated with Amazon can drain their parent's account.
I don't think the $1k minimum payout is crazy either, as the overhead of paying 10s of thousands of kids $11.32 would kill margins (leading to Robux having to take a higher %age). I'd have to think most kids are in the same boat as mine - if their games ever earn them any Robux, they'll turn around and spend those Robux in another game, because that's what they want to do with it anyway.