>>Having a startup in the US is a huge mess due to all the states and taxes,
In EU you will need to deal with VAT basically from day one (10k EUR of revenue). In US you will not deal with it until you can afford it as thresholds are very generous.
At least in Germany, this is not correct. You do not have to pay that unless: You earned more than €100,000 this year or more than €25,000 last year.
If dealing with VAT is a large problem for your business today, running a business might just not be for you, it's very trivial today to get it right and there are even platforms who basically does all the "hard" work for you. But even without those 3rd party solutions, I think the complexity is vastly oversold, it's relatively easy to get right compared to other regulations. Maybe I'm just EU-damaged already though, YMMV.