International privacy regulations and one server

Is it actually legally OK to create a service hosted in just one location?

I've seen some EU startups hosting only in US regions, but last time I checked, there are issues with GDPR when storing private data of EU residents in a US server

My first thought was that maybe EU regions are the best option to prototype an idea. But what about other countries? The EU seems to be the most regulated and restrictive, so maybe it is the safest legal option to start hosting (when using GDPR privacy views worldwide)

Do you have a list of basic regions / privacy laws to think about when building a MVP? Or at least some standard? (aka OWASP, 27001...)

My main objective is building a MVP with a basic notion of privacy concerns. This means there is a minimum set of issues a developer must worry about, like clearly marking which user data is private/sensitive. GDPR seems a practical guideline. But which ones should I consider too?

The US is a huge market to consider, and has many privacy laws, but it seems safe to store US private data in EU servers.

Russia did ban Linkedin because data from Russian citizens were to be hosted only within Russia, and also did block Telegram because any encryption must be open to the government. However I don't think most MVP are built filtering IPs from Russia. I've heard China requires apps to be hosted within China and the source to be always be ready for audition. Australia was popular in 2018 after making the backdoor law, and so on.

I am not trying to cover all the legal issues from day zero, but I also try not to start something with no concerns at all. My guess is that people just try to get something rolling, and ask a lawyer later. Are there other guiding regulations / standards you would consider for building a MVP? Or any country that is truly problematic and should be blocked?