Some of the main benefits for me are the digital elements of running a business from Estonia: being able to digitally sign and electronically submit all my forms online is very useful, because I'm a digital nomad. But even for people who still live in the US, it's actually much cheaper to start your business in Estonia: the fees are lower (and fewer) and hiring the services of an agent to represent the business was cheaper, as well.
There's also a lot of great benefits that come from being based out of the EU. For me this is especially beneficial for the eligibility to apply for a Startup Visa to live in Estonia.
Estonia has a flat tax and doesn't tax companies unless they pay dividends or have profits above a certain threshold. As for cryptos, the Estonia Supreme Court held last year that all cryptocurrencies and blockchain tokens are subject to some really dumb rules, but I still say they're better far than the US on this issue. And for the US taxes and stuff, the typical rules apply for reporting worldwide income and bank holdings above a certain threshold.