Its not an explanation for why the game is janky. Its a rebuttal to the comment that HS(card games in general, really) is bare bones or should be trivial to run well. Almost certainly they could fix the issue with background thread loading and some UI tweaks if they wanted to. That said, the issue is most likely that they're simply loading texture data from disk on the main thread. This is the default Unity behavior with asset loads and it's not really possible to hit their RAM quotas if they load every card. A subset of cards reveals information.