If an AI agent can generate top 1% supply of the atomic unit whatever your network / protocol / marketplace is optimizing for, why would you care if it was human or not? 

Value is is value.

It depends. If what you want are answers then sure, if quora or Reddit were just bots answering you get the answers. Same for an amazon full of ai generated shirts or AI books. But then why would a user need your site instead of going directly to the bot?

If what you want is human connection then bots are a burden, but so are fake friends or low effort users. 

“Entertainment” is imho more in the second case: art is about connecting to other humans otherwise it feels empty and boring.