Because they want a bias-filtered selection of the internet. It is very obvious looking at the reddit comments that most are made by bots and not humans, the difference is that most behave similarly and the upvoting favors sameness.
That’s not at all obvious to me. What subreddits do you visit? The ones I frequented had maybe 5% or less bot comments. I think mods generally banned the bots from those subreddits too.
