Been playing Battlefield series a lot more often now with BF4 just released and me playing a lot of BF3 in anticipation for BF4. Their absolute toxicity against anything with CoD is the biggest circlejerk I think I've ever run into in a game.
If you play CoD, according to Battlefield players, you're underaged, unskilled, can't deal with 'realism', a blind fanboy, have bad taste, hate vehicles, can't handle large maps, don't know class balance, don't know gunplay, don't know guns, have a bad taste in audio quality, a hacker, have a bad taste in graphic quality, can't hand melee that isn't one-hit kill, don't have no idea how military styled shooters work, never use teamwork, can't snipe, can't use tactical advantages unfairly, use tactical advantages, a fucking camper, the cancer of Battlefield, the cancer of shooters, the cancer of gaming, the cancer of the world, use overpowered guns because you suck, use underpowered guns because you don't know how the game works and because you suck, ruin this squad, ruin this team, ruin this round, ruin this gamemode, ruin this map, ruin this entire game--
I could go on for a while. Battlefield, despite being praised as one of the biggest squad-based FPSs there is, has one of the most hostile and arrogant communities I've seen in forever.