Why Do Businesses Around the World Follow US Federal Government Cryptographic Standards?

It just occured to me that even businesses outside the US follow US Federal Government standards for cryptography. Proton, Tuta, Nitrokey, and Mullvad are just some of the online privacy services headquartered outside the US that follow US government standards for cryptographic development?

I always wondered why that's the case. Why would the rest of the world follow what the US recommends to protect secrets when we use the Internet?