Shared libraries are bundled into one container, then the one container is submitted to a gauntlet of tests (service / API-level tests, e2e tests, etc.).
If you're submitting an embedded device to a gauntlet of tests, you're anyway "containerizing" all the shared libraries when you build the embedded image. Trying to build containers within the embedded image has questionable merit.
Because you can prove it. In the auto industry you can't just claim it conforms, you have to prove it does for all possible conditions. With containers enforcing that separation, you can prove it much more easily.
If you're submitting an embedded device to a gauntlet of tests, you're anyway "containerizing" all the shared libraries when you build the embedded image. Trying to build containers within the embedded image has questionable merit.