I think a lot of people initially thought the downside to R2 was a lot worse than it actually is,

Yeah, when he first got previewed I was amazed at the idea of shield regen on a falcon. Everyone else was going on and on about how steep the price was to get crits flipped face up.

Now that I think about it, wouldnt Chewbacca crew heal almost the same amount (abeit lesser) for 0 risk?

Not unless you were REALLY unlucky with R2. Crew Chewie gets discarded after one use so he discards a crit and gives you a single shield. Potentially, theoretically, if the crit you use him to discard is a direct hit, that means he gives you 3 hit points. But if you hold on to him in case you get a direct hit you might never use him at all. It is far, far more likely that he will get used for a 2 hit point swing.

Since R2 can be used every turn, and a tanky falcon can take many turns to kill, he will probably be giving you at least 4 shields throughout the game, possibly a great many more.

My friend Matt played him on a B wing the other day against me.

(bwing e2)

Probably safe to say getting a shield up twice probably won him the match