@Kerodonasium
The fact that the mc has no interest in the girls doesn't matter. They are there for the reader's benefit, not his. In fact, the mc having no apparent interest in women despite being surrounded by them is very common in works aimed a younger male reader base that is still uncomfortable with the concepts of dating and sex.
Whether he earned or deserves his powers is also irrelevent because it does not solve the problems caused by having an overpowered mc. You can give an overpowered character any sort of tragic or hard working backstory you want, it doesn't make them not a mary sue.
Younger readers often enjoy having mc's bulldoze their way through obstacles uncontested. They self-insert as the mc and get to experience a power fantasy. One example from the chapters I skimmed is when the mc faced a supposedly top tier opponent and snapped their sword like a twig. It's pure juvenile wish-fulfillment. Readers subconsciously imagine themselves in his place, proving their "superiority."
As one gets older, this feeling is flipped on its head. What was once empowering becomes patronizing. As you read more stories and develop more self-awareness, authors asking you to insert into these wish-fulfillment characters will start to feel insulting.
It's like the author saying: "Hey! You might be a total loser in real life, but don't worry about that, just play pretend that you're this super badass character I made up! He's the strongest ever! Way better than all the bullies. And all the girls want him, but he's not even interested. Everyone thinks they're better than him, but then he shows them!" It's designed to appeal to people with inferiority complexes.
If you applied your final argument to yourself you would have realized by your own logic there was no reason to read or reply to my comment. Do you really think it would be better if everyone who didn't like something simply kept their mouth shut and every single work of fiction was showered with nothing but praise? Everything ever created would be a called a perfect 10/10 and it would all be shit because nobody was pushing it to be better through criticism.
But I don't expect that you actually believe any of that because your argument is simply a very common defense mechanism deployed by people who become uncomfortable when a work they like is criticized. This discomfort is especially strong when they are worried that the criticism might be valid.