It’s more useful to consider a container an administrative separation, and as others have mentioned here, being vigilant means not trusting any one technology implicitly. Cgroups2 and libcontainer do a decent job now of separating child processes from host processes and resources, but with ai-assisted tooling will eventually come the discovery of more vulns and escapes at a more accelerated pace. In those times, when everyone is panicking, having cultivated other good security habits will bring you some measure of understanding what exactly your risks are. Containers are somewhat separated from the host os in a functional way, I don’t think your mental model is wrong, per se, but that separation shouldn’t be relied on by itself.