Gary Stu Anakin was acceptable because he was less Gary Stu and moreso just a master at the things they decided to make him good at.

Example: He didn't hop out of his ship, grab a lightsaber, and take down Darth Maul after Qui-gon got taken out. He had zero experience in combat, much less lightsaber dueling. No, instead he noticed the ship he was in was very similar to a pod racer (which his skill with was explained by having advanced reflexes due to the force, not Rey's godly level of force powers sans training). So he applied his established pilot skills to fly the ship (badly, mind you; he was still figuring out aileron rolls and whatnot, and his kill count was awful). He accidentally crashed into the mothership because of his lame skills, where he happened to be within during range of the mothership's main generator.

In short, Anakin didn't manifest unwarranted talent for the sake of being the main character, he applied his established talent as best he could and was mostly lucky.

I just want the expanded universe to be re-instated as canon and rid us of this disney nonsense.

Oh well... one can dream.

She is a huge Mary Sue, just like Batman is a huge Gary Sue.

You are never going to convince a fan of either this though, so just give up.

Luke was never a main hero in a Disney movie.

She is. It's kinda hard to say she isn't. Disney wanted a strong female hero and to do they, they created a character who is pretty much flawless. I bet she even sweats lilacs and can dunk on Michael Jordan in his prime.

Yes, undoubtedly she is a Mary Sue.

It's like the writers thought that writing a jedi was the same as writing a super hero.

It's not, not even close.
Jedi should be written as samurais. Just some basic understanding of the inspirations between SW makes this obvious. That's why the jedi feel so wrong in the new trilogy.

I don't even get the arguments that she isn't a Mary Sue. It's not offensive. It's just what she is. If somebody said "Nathan Drake is a flawed hero" nobody would say "He's not flawed! He's perfect!"

Just accept what she is and if you like that kind of character, that's cool. If you don't, fine.

Didn't she almost crash the Falcon when she got it?
Plus, I'd say that being in denial about your parents origins because you passively accepted the main antagonists' mentality that your origin matter more than who you are is a pretty big character flaw.
Also Luke Skywalker actively disliked her coming at all, Han slowly grows to accept her, only Leia actively trusts her.

She is no more competent than Luke was, and as the de facto protagonist of the new trilogy it fits that she would be generally competent.

As far as criticism goes, not only is "being a Mary Sue" a very shallow and perfunctory criticism, it aligns with some world class charlatans and mouth breathers in the manosphere. I'd avoid it if I were you, because of the stupidity by association

I was thinking the same thing about Nathan Drake.

Batman is a super hero though.

Different playbook.