I see the drop in quality over there as the more technical (the best?) people migrate to the Fediverse. As others have noted, I'm not looking forward to all Redditors coming here and dropping the quality.
Old timers like me remember the quality of Usenet prior to ISPs making it available during the Eternal September. Before then, people on Usenet were largely college students or higher. Quality on Usenet really declined when it opened up to the masses, especially after AOL made Usenet available to its subscribers.
Fantastic modern take on Goya's "Saturn Devouring His Son"!