There is no way shipping alone explains the difference.
I would suspect the majority comes from higher (VAT) tax level; possibly also some indirect overhead because Europe is a more segmented market, and needs a bunch of localization at the very least.
It's not? Maybe there is some dynamic pricing going on, but it's 79 Euro (~91.75 USD). Which would be close to the US price with Hungary's VAT (27%, which is I think the highest). Then add stuff like copying levy onto it and you'll land on roughly the same price, even with a lower average VAT. https://en.wikipedia.org/wiki/Private_copying_levy
Maybe they compared the model with the base to the one without? The one with base is more expensive in the US too though.
Hmm, at the end of July I bought a X4 Pro from them for 88.95 EUR (shipping to Spain included), seems they've raised prices since then? Lucky me I suppose.
I guess West Coast shipping from China is much cheaper