He'd be a good pick. And he has a bit more value, in the sense that he can do more. Wouldn't count on any of the 3 corners to be able to blitz, tackle or fill as many spots as Parsons. Parsons can cover also, though obviously not like a corner.
But unless the Cowboys can get a dt that can both slow the run and rush the passer, he'd be another Jaylon as far as what he actually does, spend a lot of his time tackling guys after they've already gained 4-5 yards. That's not helping the defense as much as having a better corner than Lewis, et al to pair up with Diggs....