> any modestly-visible public account I think the most visible account I follow would be Joueur du Grenier/@Frederic_Molas (a French Youtuber) with 1.3 M foll

> any modestly-visible public account I think the most visible account I follow would be Joueur du Grenier/@Frederic_Molas (a French Youtuber) with 1.3 M followers. But then I rarely check responses to his tweets. The rest have at most 150K followers and I mostly look at the answers to those with much smaller following (5k-10k). I've seen all three types of reply you mention, but nearly never below tweets from the small account. I'd guess the bots focus on accounts with bigger follower numbers than the accounts where I spent my time. I don't see any ads (only using on my browser), so I can't comment on that.