I think pretty much any game can be min/maxed. I mean, even noughts and crosses has an optimal move in any given stage of the game. And if you want to do that, if making the numbers get bigger most quickly is your thing, fine, knock yourself out.
Where it crosses the line, IMO, is when it goes from āI want to play the game this wayā to āI want YOU to play the game this way, or Iām going to be a dick to you if you donātā.
Obviously, the game can encourage or discourage this behaviour in a variety of ways. As Gordon suggests, it can make the ācosmetic metaā different from the āperformance metaā. Or it can tune what loot people get from end game activities to specifically their contribution, not the entire party performance.
If someone is just literally tagging along without doing anything, freeloading to get the reward at the end, fair enough, boot them - thatās not on either. But āI want to get this thing from this activity, and if you arenāt going to make as big a contribution to me getting this thing as I like, Iām not going to let you playā is just, IMO, rank selfishness.
I mean, fundamentally it comes down to the same issue as a lot of other stuff - some people on the internet are just dicks. But you should try not to be if possible.