Not that it's really the point of this thread, but if we are talking 6 max then this is a pretty standard UTG open range, and isn't crazy loose at all. My default UTG open range is a little looser than this.

UTG in 6 max is in no way the same as UTG in FR. In 6 max, we have position on 2 players and are out of position to 3 players. In FR, we have position on 2 players and are out of position to 6 players. This is a massive difference.

In response to the actual question, you haven't really considered at all that the 50% of hands he cbets with are likely to contain most of his equity. You have given yourself implied odds, when actually you are likely to be facing reverse implied odds when he bets the flop and you don't have a lot of nut hands in your preflop/flop range. This effect gets worse if he can bet more than one street.