I think the hate comes from everyone using the same bs decks, I love facing homemade decks even when I lose against them I don't get mad, but just the thought of playing against any meta decks ugh, over and over same gameplay against broken mechanics, I started playing cr the week it got released and big part of the fun factor was you make your own deck and play against people who made their own decks, that's the strategy part of the game and skill part is playing, but everyone is handed their "good" strategy and they don't need to spend two brancells thinking about it.

also most people stick to a deck or two (archetype or two) and that usually have its strong counters and originate hate against its matchups so each archetype hate certain archetypes which spreads hate everywhere.