Ehh... Kat can ward Hop Too, but she isn't called "OP" because of it, simply because her kit is relatively balanced in Comparison to Lee's... Lee's kit was EXTREMELY overloaded before any of his nerfs, and people saying it wasn't just didn't make any sense to me. He literally has 7 abilities. He has has 2 abilities on his Q, W, and E, and then A REAL Ultimate. The only thing keeping him in check is his tremendous late-game fall-off that makes him much more balanced. So combine this already overloaded kit with the ability to ward hop, giving him the essential ability to dash quite a good distance anywhere? Yeah, he was absurd before his nerfs.
I think Lee is fine where he is right now (maybe some very minor nerfs if anything), but if they did decide to remove his ward hopping, then I'm curious if they would do it to the others who can do the same like Jax/Kat. Also if they removed it, then buffs to the rest of his kit might be warranted. Maybe rebuffing his shield again, or something.