Visa has incentives to play by the tax rules and make it easy for the average consumer to spend Bitcoin in dollars. Most cryptocurrency credit card companies built on top of Visa aren't willing to get their feet wet, not even in the country they are operating in.
There are tax tools now. They cost $200+/year.
Isn't cryptotrader.tax free, or at least freemium?
A convincing argument would be a javascript app or a mobile or desktop app. I don't think the average person should be giving their address and personal information to a third-party.