If being unwilling to put up with people who have no business being in a m0, let alone a +11 (because they should more realistically be in a normal and read about the fucking base mechanics of just about anything) makes you toxic, then yes, you're toxic. More so, I'm among the most toxic people in the world then.
I have no shame leaving your key if you turn out to be one of those people. Like, I had patience with people fucking up hooks on NWs 3rd boss for 30 minutes straight on week one of the expansion - but I'm not going to deal with that shit if you have the audacity to go into a +15 tyrannical key without knowing shit about the main mechanic of a boss fight. If you don't respect my time, I'm not gonna respect yours. I don't care if people call me toxic for that, that kind of bitching tends to only come from the biggest failers, their labels mean absolutely nothing to me, partially because the term toxic itself has lost all meaning and is basically equivalent to people insulting each other as conservatives/leftists for mildly disagreeing on just about anything.
There's a time for teaching/learning dungeons... and there's endgame m+ keys.