It doesn't seem likely the girl time looped as well to me. It was made clear she only went to the karaoke party the first time because he was there. When he said he wasn't going this time, she said she wouldn't go either, and MC thought it was odd because he just assumes she'd have gone because...
When the raws are that far behind, it isn't a snipe.
Anyway, it sure would be nice if people in Japan gossiped. Or at least it seems like they don't from manga like this. This dude's social life would be so over, deservedly so.
The whole trading card plotline has always been dumb. TCGs have specific card quantities made for every card, and the amount he buys is a drop in the bucket for the amount needed to have a good pool of cards for proper deck building. And it feels like this plot line has taken over the story...
In a previous chapter they have the MC called Mars and Marth on the same page. It is very likely they MTL and proper nouns end up this way as a result.
I think everyone is overestimating the longevity of these new "characters". The boy badmouths his brother, the girl is overly familiar when he doesn't even know who she is.
Ayaka thinks he is making friends but he is clearly not happy and doesn't like these people.
I had to check. The last time the protagonist was seen was in chapter 35, being imapled and tossed onto the ground just before this coup attempt was started.
I don't know if this would actually work, but what about taking chunks out of the ground and/or putting obstacles in the way? Anything that would force the uniformity to break.