No it won't, did taking away true block strings from anybody else kill them?
You don't NEED to be able to hit the same string 3 times in a row on block, there should be situations where he has to bait, just like everybody else.
Kung Lao went from having soooo many guaranteed block strings to having basically 0, and his rush down is basically the same.
Also, making overhead cancelable is a terrible idea, give him a true 5050 AND plus after everything?
Liu players are fortunate enough to be playing pre patch mkx, so never had to know what it is to have fairer rush down.