Mostly it just feels odd to me that tenacity reduces everything except knockups and suppression. And you can't QSS or cleanse out of knockups or suppression. The whole point of adding suppression was so certain ults weren't completely countered by one item/summonerspell/non-ult-skill. But knockups which are added on to non-ult-skills also get this uncleansable treatment? They may only last a second, yes, but if you have 3 people chasing you and cho places a good rupture you can't avoid, that second is as much time as they're going to need to catch you. With a cleanse or QSS and decent timing you could get away from everything else, but not knockup.
why does knockup recieve special treatment over stun, snare, blind, slow, immobilize, taunt, and fear?