I guess the best answer to that question is of course a BIG NO! Granted, China is a big contributor for the rise and adoption of Bitcoin and they are primarily the country involved with Bitcoin mining due to very cheap electricity cost.
Now, the Chinese government has its own agenda and I think in the long run Bitcoin can be running against those agenda so they are now thinking of slowly disengaging and disconnecting their citizens away from the cryptocurrency platform.
I know that whatever China will decide on the impact can be heavy on the market and this is shown with the recent decision banning the ICO projects and the unconfirmed total ban of Bitcoin exchanges though it is still a rumor and nobody would want to confirm.
Can cryptocurrency still go on and have a very optimistic future even without China as part of the equation?
I really agree with your statement, as chinese cookies only get a portion of the whole piece of cake, though the biggest contributor but if china does not participate, I am sure there is a country that will replace china. ICO's actual prohibition decisions to secure its citizens from fraud, so no problem.
because cryptocurrency must still grow even though not as fast as when chinese contribute in.
bitcoin never died