True, but security breach inside a sandbox/container can cause serious damage too(stealing your code/data/keys, spreading via your code/release etc). And containers aren't for security anyway(e.g. Copy Fail breaching to host https://xint.io/blog/copy-fail-pod-to-host)

It's rare that both of those align and it is very unlikely that both are used at once. Most of the exploits (if not all) just install rce, rat and/or steal env.