Long story short:
3 independent users have 3 different own “idSite” at the same single Matomo instance, everybody with his separate settings/setup and using the initial Tag Manager Container setup and run it on the same (sometimes overlapping) web page.
According to this Embedding: Integrate - Matomo Analytics (formerly Piwik Analytics) - Developer Docs - v3 multiple containers on the same webpage are not an issue.
But the multiple trackers need orchestration, right?
Every user deploys his own container with the following settings and only the idSite is different.
Does this work or need this orchestration?
Or can I leverage the Roll-Up Plugin? Run only one tracker and provide different (url/uri filtered) views to the different users?