That's all correct and it is the right way to do things (especially from Microsoft's perspective). However, the main goal of Powershell seems to be providing a

That's all correct and it is the right way to do things (especially from Microsoft's perspective). However, the main goal of Powershell seems to be providing a scripting language that can automate Windows internals and not a shell in which you live in. Powershell is just a nice REPL, not so much a shell as you might be used from Bash. We have had Powershell for 10 years now. Has it taken off in a big way? No. The admins you mentioned use it because simple automation is the one thing GUIs cannot provide and MS had to face this after over a decade of denial. Do people get out Powershell instead of Python to do cool new projects that are unrelated to devops or admin work? Some maybe. But the real music plays somewhere else. And some of the reasons for that have been mentioned by the GP.