The hero's a Narcissist bitch
The priestess is a yandere bitch
The axe gal is a tsundere bitc- nope. She's not wrong when she said MC had to earn his keep but they're still a party... IDK there are many ways to look at it.
Conclusion => He's not chad enough for the hero's party.
It's like the author's self-masturbatory work or something, where he fellates his own self-insert for being a genius on the sole virtue of being right once and having all the answers handed to him. Because if this were an isekai/VRMMO, anyone could have just hit up the wiki or youtube for a strategy guide. No, to be special above all others, the author NEEDS his MC to conveniently receive a book that only he can read with all the answers to the game-like universe he lives in.