Earlier quoted context omitted.
> Simply put, yes. Feel free to build such services, if you wish. > You are maybe concerned with the technical issues / problems to the service provider. Not just that (though I certainly don't consider it reasonable to expect a service to have thousands of servers in thousands of jurisdictions and deal with thousands of legal systems; frankly, I want services to expose themselves to as few jurisdictions as possible)…
> Feel free to build such services, if you wish. Well, I don't propose or expect companies to volunteer doing this. My point is that EU (for one) should mandate them, and if service providers like FB, etc, don't like them, they could skip the 500m market -- and just be careful not to let the door hit them on their way out... > Not just that (though I certainly don't consider it reasonable to expect a service to have…
No, not at all. I expect it to be the jurisdiction of whoever runs the service. That jurisdiction will necessarily have control over the authors of the service; there's no getting around that. (The authors can try to build the service with themselves as a threat model, which few services do, and even then that may not work.) Unless you want to mandate that people can't use services from outside their country (and enforce that with a country-wide firewall blocking access to the real Internet), then you're never going to get around that.
Also, you seem to be treating "store and use data locally" as a thing that protects the citizens of a country, rather than a thing that threatens the citizens of a country. Many countries want data stored locally so that they can seize it, and want services hosted locally so that they can block those services or make them consistent with the country's propaganda.
Also, you're assuming that data is nicely partitioned by user. For many useful services, it isn't. Just for the simplest case, consider collaboratively-edited works by multiple users.
> There aren't "thousands of jurisdictions and legal systems".
Tell that to states and equivalent sub-jurisdictions within countries. Tell that to many large cities and their local regulations. Thousands is if anything an underestimate.
> there could easily be an infrastructure and common services to deploy to span the globe
That sounds like a great way to introduce security holes and a vastly expanded threat model.
Also, to comment on something you edited into a previous comment:
> (Exceptions could be made for non-democratic countries -- no reason to give control of a service's local data to a dictatorship).
Who gets to decide that? Obviously not the countries themselves. That just leaves the people building the service and the people deciding which services to use; those are the same parties who already get to decide that today.