I gotta admit, this series doesn't hold the same level of anticipation like it used to. It's nothing new, but seeing Hibiki win that board game with such a ridiculous margin... it just feels like bad writing. Such things are fine, but the fact that the author hasn't defined exactly how this happens.... feels like fanfiction level.
I do agree with your feeling about the quality of the writing, but I do believe it's written this way as a thematic device.
Last chapter comments I had an argument with a guy called SSSR about the author's picture of Genius and who we are supposed to identify with, whether we are supposed to want to and aspire to be like Hibiki, and whether we can actually achieve it.
Thematically, we have Hibiki, the gifted genius who wins overwhelmingly even in games of complete luck. Even when others get close to her, Hibiki just pulls even further ahead. And then we have Saki, who takes the 'normie but works hard' position.
Having read ahead (as the translator, apologies for the delay on behalf of the team haha), this next arc is beginning to ask questions like, "We all aspire to be like Hibiki. But where does success come from? Can we really be like her?"
So story-wise I do agree that it's basically the now-boring isekai trope of overpowered MC. But theme-wise I think it's really building towards the author's view of genius.