Said this in another thread about Wattson, but it applies to more than her.
Low profile is a stupid, stupid way to address problems. It doesn't solve what's wrong with the hero. Wattson was never chosen a lot because she actually takes thinking and learning to use. Some teamwork as well.
But let's say you go with that she was somehow OP...she was OP because she could fence? Her ultimate? Low profile doesn't stop her from using either.
So you can see what happened, Wattson was used even less by people who didn't want to bother with her, and is not used any less by people who do.
It was a crutch nerf, a bad one at that. It's more of a pain and an insult to people trying to learn how to use her, than stopping anyone who does. Dumb.
Look at Wraith, who happens to be a low profile character. She's still used a lot at top tiers, but she's used somewhat less at low tiers, definitely not an auto include for average players. What stopped that? nerfing the problem with her, which was too much Into The Void. She's far from useless now, but the nerf fixed what the problem was with her.
Low profile should be saved for characters it makes sense for...you know...characters who are Small with a Low Profile. Not as a crutch nerf.