Here's an example of a bot account that has an outsized influence on niche political subreddits:
This is an irrelevant tangent, but bots reposting content which previously was highly upvoted reminds me of exponential backoff in networking. The reposting serves as an automated way to maximally spread popular content to the widest range of website visitors, until the value of additional reposts diminishes and the bots reduce their reposting frequency on that item because it's no longer hitting the highs.
It probably doesn't work out that way in practice since the karma farming bots may not be that sophisticated, but I think it's a cool idea at least.
I wouldn't go so far as to say reddit has been taken over by bots but I've started to wonder more and more about it.
I generally feel like things have subtly but noticably changed for the worse since the exodus but I can't name a replacement in general except for some topic specific forums here and there.
On the bright side I do think the new UI has improved noticably. I still revert to the old site often but the new site is better than it used to be.