I think with the interest crypto is getting from institutional investors, those active in the game will almost definitely have to register their addresses and link them to a personal profile. I don't think the government will be able to cover all crypto, but the big crypto coins will probably be covered. While there will be some resistance, I think the "smart" investors may even push for this as it legimatizes the crypto as a medium of exchange/asset amd further pumps up the price.
I couldn't agree more with this. I think the natural extension of the transparency of the blockchain is that eventually it will enable monitoring of individual wallet addresses. That said, how long it takes for an organisation like the ATO to catch up with the technology required to actually enable this to happen is another question altogether.
I do think it will be a good thing longer term though if it happens. As you say, it will lend legitimacy to the entire system, and with legitimacy will come greater adoption, both as mediums of exchange and as investments.