You're both moving the goal posts (if powershell were superior I and countless other people would absolutely chsh it for our accounts, since we're already not using bash anyway) and not making much sense. Many sysadmins tend to spend a fair amount of time doing command line stuff and/or writing shell scripts. If powershell offered significant enough benefits for either, of course at least some companies would standardize on it, just like your hypothetical company presumably standardized on using containers to run their 10k services rather than installing some custom k8s cluster to satisfy the whims of one individual infra guy.

When one doesn't have control over the repositories used in build and service machines since they are locked down nor have control over what goes into docker images (only secured images allowed and good luck trying to get your custom tools in), one will use the stuff that is already present.

This is far more common than you think in enterprise corporations. I work at the hypothetical one, which doesn't use k8s. (yet to upgrade cloud infrastructure of native data center)

If power-shell was bundled by default in Linux distro LTS releases, a lot of sysadmins I know would start using it, since they are already familiar with it for windows and write all their scripts in the same.

Meh for argument. Its not like 100% of people are "SSHing into 10k containers to run few commands". Its probably less then 0.00001%.