I expect that what is gradually happening on the subreddit is the people who were only participating for one or two playthroughs to see what it is like, or only participating because its the new thing on twitch have been falling away and so their voices on social media is slowly giving way to the same crowd on the forums here. Hard to prove overall, I guess you could try to do some correlation based on the themes of what is posted at different time intervals by scraping the subreddit, but thats too much work for a mere idle curiosity. Looking at what stats are already scraped was somewhat amusing, especially for
top keywords.
The same thing happened on the forums, although it happened much faster. Most people don't care to argue the same points over and over in circles for months on end, so after they have had their say, they just trot off and do something else. If you look at the forums now, by and large the people posting on every thread are the same group of people and the discussions inevitably fall back to the same topics. I was half tempted to make a bingo card of the threads here, but I thought I had better not because someone might get offended. Still, you could make a drinking game out of these discussions quite easily where you take a drink every time someone calls BG 3 DOS 3 or they make a comparison to Solasta. You might want to pick a drink with a very low concentration of alcohol though or you might die from alcohol poisoning.
Early on there were quite a few people constructively arguing different viewpoints, but they have since moved on.