Gaming and gaming, and politics is politics. Blizzard are right. The two should be kept separate. If you want to make a political stance or announcement, you should do it in your own time in an appropriate forum away from the competition, and face no repercussions. To use a gaming platform for your own political agenda is out of bounds !
And besides, what is going on in Hong Kong at this time has NOTHING to do with democracy anymore, and is yet another blatant western back attempted colour "regime change" / destabilization operation.