These are the members of the
OECD and its Centre for Tax Policy and Administration : Austria, Belgium, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Netherlands, Norway, Poland, Portugal, Slovak Republic, Slovenia, Spain, Sweden, Switzerland, and the United Kingdom.
So they are not representing the whole world...
In any way, most countries have already defined Bitcoin as a Commodity and
Capital Gains taxes are already levied onto Bitcoin profits. (In some countries losses can also be claimed) There are some exceptions that allow Bitcoin to be used as a currency or a payment option.. where they then charge VAT on those transactions.