Bit boring, isin't it?
Like why should I really care about a dude who wins all the time? Not that much of a hook. If you REALLY wanna talk about it, let's talk about how a lot of those Power Fantasies/Isekai stories are extremely misogynistic! Using women as a goal to achieve or just a "reward" for the protagonist just being so cool. It's wish fulfillment. Which is fine, but I wish they saw women as... people in those stories.
Typically, those stories, especially Chinese stories, have the MC collect women like Pokemon.
Almost all of them actually forget the earlier women and "side pieces" after a few hundred chapters, which makes it even dumber.
Though I wouldn't say this alone defines the power fantasy trope.
I think it can be well done, especially if the MC actually earns their progress.
If the MC struggles and has to really earn every single improvement and just doesn't calmly beat up anyone in their way with everyone around him clapping and admirers going crazy over him, it could be a great story.