Thats just not true lol. Kass is in a balanced state right now but there was a day where Kass would riftwalk onto a squishy target, drop his combo, insta-kill them, then zhonyas. When his zhonyas was over he could just riftwalk back out or on to his next target. It was impossible to focus him down, chase, catch him out, or escape from a kass and he would just hunt you down even after you flashed away. Nobody could 1v1 him which made split pushing impossible because he would come and run you down. He had insane carry potential on top of the insane mobility which gave him crazy roam potential, pick potential, map pressure, and team fight presence.
He was literally pick/ban from LCS all the way down to Bronze with everything in between. He literally had a 98% ban rate because he was so busted. Now that he's in the middle ground where he isn't an absolute monster, people want him buffed again because they don't remember what Kass is like when he's strong?
Kass is absolutely fine and is in need of absolutely ZERO buffs what-so-ever. People don't remember shit man I swear. Then we have people like this who are saying Viktor is as mobile as Kass. Lmao.