Gallinari got 42M/4.
They are both 23 and Gallo had better numbers on a better team.
Batum is a nice 3rd option and still has upside but 50M/4 is crazy.
Something like 36M/4 seems fair IMO.
But Gallinari wasn't a free agent. Free agents almost always get paid more. It's how it works. You can't compare a free agent contract to a non-free agent contract and say "look, that free agent got paid too much." They go to the highest bidder, more often than not. Of course they're going to get paid more, because teams try to figure out what other teams are offering, and try to offer more, so long as it fits in their budgets.
Now, I'm not saying Batum at that rumored offer isn't a bad deal. I don't think I've seen a Blazers game in a couple of years, so I have no idea who this guy is other than someone I remember people on this board wishing the Celtics would draft a few year ago. But in general, the "XX-YY dollars for Z free agent is insane" meme that floats around this board often seems a bit naive. The salary cap/contract maximums artificially deflates the salary of the top players and rookie contracts, making the second-tier players seem like they get paid too much. Certainly there are some third-tier players who get max deals, and yes, those are foolish, and maybe Batum is a third-tier guy. But people just yesterday were decrying the amount paid to KG, and in virtually every FA thread you find on this board, you see this line of thought.