I thought it was an ironic thing to make fun of people who're self entitled and that its hyperbolic. Then I had one in a dungeon a few months ago.
It was dumb. It was the last boss of Keeper of the Lake, the tank didn't tank the dragons in the right place and we also wiped. No big deal, it happens, people make mistakes, people aren't as experienced or don't always know mechanics and so on. And the tank mechanic in question is not immediately obvious. So I explained them in what the mechanic was and I thought I was quite pleasant about it.
They flipped out about how I was telling them how to do their job and were very rude and defensive about it. I told them they didn't need to be rude because I didn't think it was an obvious mechanic, they didn't do it and figured it's quite plausible they might not have realised. A friend was in the group who backed me up on it. At no point did we put them down.
Then the guy just continued to run his mouth of and being an a***hole and included the line, "I can do what I want, you don't pay my sub".
And fairplay to him. He doesn't pay ours. We kicked him and got a tank with a better attitude in his place. Win for that tank, nice quick roulette. A***hole tank on the other hand wasted their's.