[user5994461]

It took a while for powershell to be installed on most computers. It's still certainly missing on many computers (i.e. the oldest and most vulnerable).

I actually don't know whether it is installed as default in the latest Microsoft OS and patches.

That and the very easy way to analyse/reverse engineer scripts don't make a great candidate for malware.

Anyway, the windows shell is enough for trivial scripts, and one might as well write software in a real programming language for the rest.

[contextfree]

It's been installed by default since Windows 7 and PS v2. The only version that wasn't installed by default with a Windows release was PS v1 (introduced at the same time as Vista).