But he is obviously in a better structural position than most classical IQPs, as his light squared bishop is open and he has complete control of d5. He should be fine if he can fix all of his short term problems.
In my chess base I only have games from before 2008 (for some reason, I need to reload the database), but there is only one game where a player rated 2500+ lost the position after Bxd2 Nxd2 d5 exd5 Nxd5 Qb3 as black (and he was rated 2519), while 14 of the games are wins for black, and 35 were draws. I think that speaks for itself.
Chess.com style percentages among 2500+ players before 2008:
White wins: 2%
Black wins: 28%
Percent score (for white): 37%
I can say I would never play this line for white, even against an opponent rated 500 points lower than me. It doesn't matter if I can play it for black, as it is not in my repetouire.
once black fixes his pieces I believe he should be better.
Black's problem isn't "fixing his pieces", but rather managing white's initiative which is mild, but persistent.
You should have a look at some IQP literature. Black's problem is durable, which at the amateur level means that it lasts until white self-destroys his position.
I know that you have much more experience with these types of positions than me, but I still feel like you're over generalizing. This position is not the typical one found in IQP literature.
Oh, it's quite typical. The only anomaly for white is the positioning of the queens knight (it should really be on c3). It's equal, but white has a mild initiative.
But isn't it also better for black to have a c7 pawn instead of an e6 pawn? Or just different?