I am not too worried, especially considering how flexible derivative payoffs could be and how tricky it is to enforce these types of things (e.g. someone can list contingent premium options that would have zero premium at the trade time, swaps on return levels etc). In the worst case, derivative volumes will move off-shore and local stock volumes will decrease (it has happened in Sweden and is in progress in India, for example). My expectation, however, is that the potential proposal will be conservative and the final result will have plenty of loopholes.
You're more sanguine than I. Hope you're right. An acquaintance in DC tells me they'd like to close the offshore loophole by taxing US taxpayers on securities transactions wherever they occur. How that would work, I have no idea, but note that the US is one of two countries in the world (the other being Eritrea) that taxes citizens on worldwide income, so if there's a way, I'll count on them going for it.
Make no mistake: There is a hunger on the American left to go after evil "speculators."
Btw, re: AOC's Twitter clout, here's an interesting metric:
https://www.axios.com/ocasio-cortez-dominates-twitter-6a997938-b8a5-4a8b-a895-0a1bcd073fea.html