1. He just seems to be having so much fun so far with his BYU experience. He's got such a wholesome personality and has been a great fit for BYU on and off the court. He might want to keep having the innocent fun experience he's been having for another year, because even with all the money to be made in the NBA, there are some things he might be enjoying about his BYU experience, the culture and relationships, that money can't buy. That is to say, NIL money could be sufficient for his desires right now.
2. A chance to obtain further development (e.g. improve shooting percentages) AND team up with AJ Dybantsa (assuming he does commit and sign with BYU). Can you imagine the two of them playing off of each other? The passes and assists that Egor could make to AJ...(shivers)...That duo together could solidify a 1st overall pick for AJ and top 5 pick for Egor in the following year's draft. Maybe even as high as 2nd or 3rd for Egor.
3. I'm not so sure Egor isn't already dating someone on the women's basketball team, or perhaps he might have a crush on them anyway. I'm not certain of it, but there seems to be some signs out there that this could be a possibility. Emphasis on COULD BE. I'm not gonna name drop who I think is the possibility here. I'm only mentioning this here because it could turn out to be an additional reason he could consider returning, if my suspicion turned out to be true. I could just as well be very wrong on this one though so don't hold me to it.
The first two reasons could be reason enough.