Why do people avoid getting better at the game?

[Jojoya]

then maybe dont play a multiplayer game? especially not one that has a ToS Clause that says if the majority of your group doesnt like what you do, you can get the boot

ToS also says that action can be taken against the majority if their decision is made under a pretense that violates the ToS. The majority is not always assumed to be in the right.

This is sounding like one of those scenarios where the person is like "You aren't playing as well as I personally think you should, therefore you are bad."

That's just your opinion. If they completed the content, then they have done the minimum needed

Not necessarily true, though I suppose that depends in part what you consider the minimum needed.

I've definitely encounters players that were a hard carry through MSQ content. I had to solo the last half of both Beatrice and Scarmiglione in Troia the other night because the rest of the group was struggling with the mechanics.

Personally I don't mind helping out players who are struggling as long as i can see they are trying to help as best they can and have a good attitude.

I also understand (and to some extent agree) why some players don't feel they should be expected to do the same.

It is however SE's call on whether such players should be allowed to continue to advance through the game. Duty Support, unfortunately, is not always a helpful solution.