What is the primary point(s) of building bots that do this kind of thing, that seemingly flood the internet with its own Great Internet Garbage Patch?
Existing businesses did this with live humans.
Ranking/review sites for B2B services would work with paying customers to solicit interviews and reviews from their customers, and of course only the 5 star reviews get posted.
Heck, a lot of these "bots" may actually be a real human working a table of 100 cell phones in some cheaper country.
Why not do it? It’s essentially spam / pollution, and there are no consequences.
It is always money. You can sell “I will get your launch to top 10 in ProductHunt.” Yes if/when taken too far, everyone will ditch ProductHunt and it will die, but until then, a quick buck can be made.