I cant even imagine how to track a person who has a cryptocurrency. If, of course, the person himself came and said all his data or trades large sums, then this may attract attention in transactions from his wallet. But people who trade not large amounts of cryptocurrency are not worth tracking.
I think they are only taxing the cryptocurrency exchange, because for me there's no way to know if you are a crypto user or not, you will just get caught when you broadcast it to the world haha, but yeah I think the crypto exchange is included and those who are running a business.
I think that the United states are accepting it more as digital assets and which people are using to trade, and since it is taxable, they are more concerned about the tax itself which is what will be their own benefit and I think that is good anyway, at least, that will serve as bribe for them to allow us too to be able to use our cryptocurrency peacefully lol.
I think that they felt they cannot have control of it before, but now that they know it can be regulated and they can still get what they have been getting from fiat through its usage, they want to regulate it and which I think is the reason why they have tried to invite binance to establish a separate platform for their own citizens where they can have full control over the income of their people through binance exchange.