Guys, just found the Lesse message in telegram chat: "we have to exclude these countries because the regulatory requirements in these countries are different and we would be subject to legal requirements that we are unable to meet today. however, i'm not an expert in this field either and i'd like to ask our legal expert again!"
So this is definitely the answer. Didn't know that USA has already some regulations on crypto.
The law had targeted crypto like 2 years ago and there was a lot of changes in the sphere since that.