I remember when I first started noticing bots bad was in 2016. They have been there for a while now. It's advertisers turn now though. It's at the end stages
The Obama AMA was in 2012, That to me is the turning point for reddit, it's when it's population exploded overnight (which meant old users could no longer enforce cultural norms for the platform), it's when news media really started taking the platform seriously and I think when a lot of the political influence of reddit was realized.
Makes sense. I noticed it was bad because it was obviously election related and completely off topic for the subreddit. So it went past the high quality into the simple and bad
I got a huge strike, which eventually led to me being account banned from Reddit (seven year account, 600k karma) for calling out Israel for the pogrom against the Palestine people. Reddit is really trash now, most of the reference questions are 2+ years old.