The only issue with this is, At what price to they determine the tax you owe. Is it the highest price the currency got to, what you cashed it in at, The lowest price and over what period. Do you pay tax on all your currency at the same time. With having more then one currency does you tax get paid on the currency which done well, and no consideration for the currency you lost on.

Which ever way this goes it will give advantage to Corporation and Financially secure institution, Through new law and legislation. In the end, If crypto is controlled by an external entity, such as a Government, Financial Institution or private entity, The cost will return to the tax payer and tax exemption for the company