I raided in D1 a moderate amount (something like 55-60 raids in the 9 months I played, mostly hard mode). I LFGed every single one of those raids and very rarely encountered toxicity. You really just had to avoid the guys mandating "Gjally or boot." I'm lucky to have a raiding team now that I've returned to D2, but my experience with LFG before finding that team was really negative. There are still good people and good teams out there, but it's less frequent that you'll encounter them.