Haven't finished the show yet, but just FYI this isn't something the studio can do anything about. The studio doesn't decide it wants to do this season.
What likely happened here, is that the Publisher of the Manga or some other company on the production committee commissioned a second season after the first did as well as it did and the Manga wasn't far enough along during the season's planning/production for them to be able to fully follow it.
That's likely the reason why the show goes anime original.
If you wanna get mad at someone for "disrespecting" the Manga (which I think is a bit of a ludicrous take tbh but to each their own), get mad at the publishers and the other companies high up on the production committee, not the studio.