This site has the vaporwave neon and the intentionally shitty gifs (like the Under Construction one that used to be the landing page). The website for r/SubredditDrama is intentionally disastrous (it’s rdrama.net, but be warned it’s even more full of brainworms than the subreddit). A lot of sites will use chan or PhpBb boards. Even the plug-and-play Reddit alternatives have universally opted for the “old” Reddit style combined with whatever nightmarishly boomer custom CSS their ancestor community used to have.
Maybe this point seems obvious, but I think there’s probably more to it than “current Internet sucks and the old internet looks good by comparison”
Elder tech folks had such high hopes for the internet. It was established dogma until very recently that the internet would topple all the authorit*rian reg*mes around the world. A return to old aesthetics is perhaps an attempt to revive this hope.