The difference this time is that blockchain companies are relatively easy to start outside of US, and other countries will gladly grab the market.
EU will allow kickstarter-style equity crowdfunding from July 21st this year, up to €1M (accessible to general public, not just "accredited investors"), and - depending on a state - equity crowdfunding up onto €8M with minimal paperwork.
Plus, there are simplified rules for handling security tokens in some of the countries. If memory serves me right, setting a crypto exchange dealing with security tokens in Germany costs ~40k€ in license fees, and ~400k€ in all legal expenses. If you have it in one EU state, you're allowed to transact in all of them, and all the rest of the world too (US excluded).
Worth noting also, that unlike webtech, in fintech you can build a feasible business while banning US. It hurts, but it's doable - especially when US startups cannot compete :)