Sion (Post Rework) Suggestion

I noticed that Trundle's e, which creates a small piece of terrain and a slow around it, doesn't top Sion when he hits it during his ultimate. When Sion hit's the terrain head on he just seems to slide around it instead of hitting it and and getting stunned like normal terrain. I just thought that since it's impassable terrain he should get stunned when having a head on collision with it.