I don’t during the bench press. I think injuries can occur when using lots of weight if you let your shoulders move around a bunch. Virtually all of the big benchers keep their shoulders pinned. That isn’t evidence in itself, but it does seem to work.
For rows I wouldn’t try to keep them pinned in place (I don’t think you will be able to if you are using enough weight).
For something like a deadlift where the shoulders shouldn’t really move anyways, you want your shoulders as low as possible (this effectively shortens your torso making the lift more efficient). I also wouldn’t try to pin them back, because doing so will make your starting position worse (more bent over). You will also likely lose that position and when that happens you lose overall position, and the bar slows. It is something (shoulders back) beginners try to do IME.