>>13297425Some time ago this board became noticed by /pol/ and other groups of outsiders that are not actually especially interested in science or math. Their numbers are so large that they quickly overwhelmed the amount of competent posters. Covid-19 and the vaccine multiplied this effect because a lot of shitposters from other boards came here to spam and fling shit around. /sci/ has always been a slower board, so it didn't take much for low quality threads to completely overtake the good ones.
There is also the phenomenon where high quality math/science posts require much longer. It takes only a few seconds to write out a shitpost, discussing theory requires expertise, knowledge, and effort. So good threads will often fall to the lower pages and die out before ever getting many replies.
I imagine many competent posters left for greener pastures long ago. There are still great threads every so often, usually when the OP actively works to keep it alive and 1-3 interested anons make an effort to keep engaging with the posts so that the thread keeps getting bumped.
An example is the cellular automata thread that was up some time ago.
The final issue is the lack of active moderation on this board. I highlighted this a while ago by making dozens of trash quality threads. Most of them remained for 14+ hours before being deleted.