isn't that just speculation? So far the "unlocking mythic powers" thing with MC has been strictly related to only Nefari content. I don't recall that even getting mentioned in the content for any other girl. Now granted - it seems that unlocking such powers would be a big life-changng moment in the life of a character, impacting nearly all aspects of their life, but that doesn't guarantee that the game will actually end up written that way. After all, the game is a sandbox in which we as the players choose what content we follow and what content we ignore, as well as the order in which we do it. It would be weird if suddenly players who ignored Nefari had scenes of MC using his powers, in the content of the other girsl. And getting a big fat "you must reach Nefari level XX to progress with this girl" message would just piss off those people. Yes, there are requirements for optional content like that, but it's *optional* and usually for the sunday events.
Or are you saying that all the girls are going to Egypt with Nefari and MC? Because I don't recall that being suggested in the last update, and some of the other girls already have scenes of going on a trip with MC, just the two of them. For Nefari to take everyone on her event, especially since the real reason for the trip is to "borrow" something from her parrents' lab, would just be poor planning. The suggestsion seems to be that once the item is acquired, they will need to bail out fast - something much harder to do in a big group, especially since one of the members of this supposed group (Esther) is prone to fainting in intense heat (which Egypt is known for).
I'm not hating on Nefari. I'm just pointing out why folks who enjoy this game for anything/ anyone else than Nefari are going to have a problem with this.