There’s an important distinction here. Most of the comments you read. You being the general you. Most people will read a few dozen comments at most. These comments are overwhelmingly written by bots or inauthentic participants in subreddits like r politics. And they’re the most visible because these same groups also upvote them inauthentically
I just don't think that's the case yet, but we probably have no evidence one way or the other.
I don't know about /r/politics since I don't read it, but say in /r/worldnews, /r/europe, /r/ukrainewarvideoreport, /r/noncredibledefence, when I open a thread and pick ten comments at random and then take a look at their user histories I believe most are human.
I don't think that's true yet. At least regarding the portion of comments written; I have no idea about the votes.