Carlsons arb salary is a pittance slightly over league minimum, in the bench player territory. It is not “high” at all.
He has establish enough mlb PA’s to earn his base arb salary, but it’s with a catch, he needs a buyer for over league minimum.
If Carlson was a good arb player, in his class, 10 to 15mil is on the table. But, the arb system agrees with you, he’s been poor.