Oh, that is totally fine by me - as long as the person in question is still able to perform on a very basic level of "well" in groupcontent.
You are again making excuses for why someone might not do that - or you're assuming that my expectations of other people are high, because my personal goals are high.
But is it really a high expectation for a tank in a level 70 dungeon to make sure they've got aggro on all mobs? For a healer to keep said tank alive and heal through group-wide AoE? For a DPS to know their single target rotation and their AoE one and to know when to use which? For everyone to move out of AoEs, stack with stack-markers and turn their backs when a giant eye appears?
I get the different approach and everyone can approach this game the way they like - until they enter group-content. The moment they do that, I feel it can be reasonbly expected that they perform with a very basic level of competence. The level I just described. There is no excuse for not doing that, no matter how hard people try to find one.
Explantions? Yes. But they dont make for an excuse.
Even the person only playing one hour a month plays this game together with other people and should be as mindful about them as they should about that person. Just "doing whatever" in a dungeon, not caring about your performance, not listening to advice given isnt being mind- or respectful. And thats the person I'll have an issue with - one that can be solved by kicking them. Not because they were performing bad, but mainly because they displayed an atiitude of "I dont care about my fellow players".
If you can only play an hour a month and dont know how to play your job anymore everytime you log in, you should take the 5 minutes to figure it out again, before you queue for a dungeon.
People need to stop making up excuses for someone not being willing to even read their tooltips...