The battlegrounds client is… tragic.
It’s like 30% of games you either disconnect, the combat timer doesn’t speed up so you have 15 seconds to take your next turn, the client freezes up for 25 seconds when you play a card etc.
I play a lot of different games and none of them come close to being as laggy/buggy as this one.
A big difference with other games like League that fixed their client (and broke it, and fixed it, and broke it even more) is that the client is not separate from the actual game, which means they can’t just redevelop an entire client and plug it to the game. Which means that they have to deal with whatever spagetthi code that was originally developped 17 years ago.
Even if nowadays they made great improvements, they are still tied to that core that limits them.
For example that’s why it took them so many years to allow to reorder decks in the collection, not because they didn’t want or didn’t think of it, but because it required a major reworking of the collection code.
At least, that’s the explanation I hear given by people in touch with blizzard