So let's go:
1) Bitcoin exchanges are not licensed: OK, a license requirement would happen to exchanges in most countries of the First World, too.
2) Here I quote a bit more, because I consider the argument a bit weak:
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“The mechanism of limiting the amount of encrypted money by specific code is controversial,” Professor Yang claimed, citing how a “new encryption system may be invented, the existing algorithm can also be tampered with, the issuance of encrypted money may also increase.”
I think his main point is that there could be, at some point, more than 21 million Bitcoins created by miners. So he's ignoring the game theory considerations that practically avoid it - a crucial point in Bitcoin's concept.3) Price volatility:
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“because there are no economic fundamentals to assess the supply and demand of bitcoins and intrinsic value, the market speculative atmosphere results in sharp fluctuations in prices.”
Volatility is actually a problem, but in my opinion there are "fundamentals", and Bitcoin is not essentially different than, for example, stocks. The Bitcoin Ecosystem can be seen as a large "organization" containing all companies, organizations, groups and individuals that use Bitcoin. It's "intrinsic" value is not totally arbitrary like he claims, but can be tracked by observing indicators such as the transaction rate, the number of businesses related to Bitcoin, surveys about Bitcoin usage, etc. (although not in an "exact" way).4)
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cryptocurrencies are “not affected by the driving force of inflation and the exchange rate difference as well as other issues.”
That's the classic anti-deflation argument - debatable, but I don't share it.5)
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[Cryptocurrencies] can be used for money laundering and financial fraud, as well as to avoid foreign exchange controls
Again, a typical argument of an authoritarian state which wants to control everything what their (subservient) citizens do.6)
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some pyramid schemes and fraudulent activities leverage digital currencies.
Cryptocurrencies are not drastically better suited for pyramid schemes than cash, but they can grow more rapidly on a global or regional scale. Here he may be partially right - but I disagree that a prohibition is the way to go, education is.7) Market manipulation:
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Anyone investing tens of millions of dollars will be able to easily manipulate the price
True, but that has nothing to do with the nature of cryptocurrencies, but with the low liquidity on the markets. Better systems to track the Bitcoin ecosystem (businesses, users ...) could help.
8 ) Security risks: These are inherent to every form of "digitalized" money, even credit cards, not only to cryptocurrencies. Very weak argument.
9) Darknet markets: Again, understandable from a state that is a "control freak", although Bitcoin transactions can be tracked relatively well (we have seen it many times when some markets were "closed" and their founders imprisioned).
