The key concern of data location is:

Retrieving data for legal authorities addresses legal hold and e-discovery obligations, which is a separate compliance concern from data location.

Preventing prohibited parties from accessing data is an access control concern, not a data location concern.

Storage redundancy and high MTBF relate to availability and reliability engineering, not to regulatory data location requirements.

Regulations such as GDPR, HIPAA, and national data sovereignty laws specify where certain categories of data may and may not be stored. The key concern of data location is therefore ensuring that data at rest resides only in geographically and legally permissible locations. Violations can occur simply by storing data in a non-compliant region, regardless of whether it is accessed or disclosed.

Data commingling with other customers is a multi-tenancy and data isolation concern, distinct from the regulatory question of where data is geographically stored.