I'm not worried because I made best effort to report and pay taxes properly on my crypto holdings just like I do on my other investments.

I really don't see the big deal here. People who were thinking that crypto was going to magically be exempt from taxes were delusional. The only open question is if the IRS may change crypto->crypto trades to like kind. As of today with the current guidance though, no - crypto is property similar to a stock.

Coinbase has already issued tax forms for those who owe capital gains taxes because of cryptocurrency sales. So this isn't in any way new or unexpected.

I don't think that is correct. They are issuing 1099-K's for people who are accepting Bitcoin payments through Coinbase. They haven't issued any 1099's for people who only have a capital gain from buying and selling.

True, but they did add some tools to the tax center tab to make it easy to calculate your gains/losses for tax purposes.

The definition not accepting payments is broad, though: if you made a profit trading alt-coins on another exchange and cashed out using coinbase, you get a 1099-K.

We used Coinbase purely for trading and received a 1099-K

> if you were American, had a coinbase account, and made significant capital gains in the years under investigation, would you not be worried?

Well since I wouldn't have committed tax fraud (and potentially other felonies) by not reporting capital gains, I wouldn't be the slightest bit worried, no.

As if tax loopholes are unique to the gop. I would wager they are pretty evenly distributed between Democrat and Republican. Not to mention corporate and wealthy donors.

Lots of people in the circumstance you describe will have made a good effort to pay appropriate taxes.