You're making the assumption that people who put effort into the game and their characters somehow don't have fun. While everyone has their own definition of what constitutes fun, I'm honestly scratching my head of your claim that doing anything at endgame in this game is even remotely similar to work.
You're free to have your idea of "fun" all you want, but if you are doing group content with others, it's no longer about you and how you have your fun, its now about the other 3/7/23 other people you are playing with.
If your idea of fun somehow hinders the group from progress, chances are you will be replaced by someone that doesn't use the guise of "fun" for being unable playing their characters and the game at a acceptable and competent level . End of story.