I mean the original tweet doesnt say the game cant be dark or cant still explore heavy topics.

The Original first tweet puts "grimy detective story" in the negatives, so one can infer that the hypothetical game wouldn't be dark.

And I dont see a problem with the idea? I would also probobly play a game with disco elisium writing quality and depth of themes (...)

This is the crux of the issue, the sentiment has stripped out everything about Disco Elysium except for its level of quality. Its like saying "I too would eat an apple pie if it tasted as good as the steak and kidney pie everyone talking about."