How is that relevant to data storage, locality and access now? Secure endpoints don’t have to be managed by huge companies running data lakes which could be anywhere.

The current best security practices can be used by any organisation. I respect the engineering that Google have done. gRPC is excellent and local first software can absolutely use it, accessing data locality verified endpoints.

In my experience, the best practice for sharing "health data? Government data? Corporate data? Financial data?" within an organization is to use a secure cloud platform with native data sharing functionality. The original comment's suggestion for "local-first software" doesn't work, because organizations frequently need to forward private data between individual workstations and the staff are going to do it using email if you don't give them something better.