Why can't you cleanse Malzahar's ult?

I mean, I guess I never tried it before the rework, but I know for a fact that you can't cleanse the ult now. Not even the damage needs to be taken off, just the stun. And I understand that it is a "suppress" but still.

EDIT: I meant this as more of an "I wish cleanse would work on his ult", because at the moment it has literally zero counterplay. Not that everything should, but something that powerful - when the rest of his kit is already reasonably strong - should have something you can do about it.