While aluminum isn't nearly as tough as steel, that's not much of a bend to straighten it. The elongation percentage of any given area in that rack is probably quite small, bending it back would weaken plastically deformed areas (fancy way of saying bending it permanently), but not by a whole lot.

Aluminum racks typically break at the welds, or at high stress areas like attachment points. If you do bend it back, do as others have noted, start with a little force and work your way up until the rack is centered on the bike. Check the attachment points and welds afterwards.