Imo this kind stuff probably because these "dev" having safe space on those discord servers rather than using something properly setup site/forum.
Heck you can make your own documentation using github/gitlab built in wiki or if you want something fancier, setup a site using JAMstack/static site generator, pick suitable theme then use gh page to host it.
I even more hate this stuff when the files is gated inside discord server, dude out of all possible file hosting services why the heck you would use discord?