PowerShell variable names and function names are not case sensitive.
I understand the conventions of using capitalization of those names having specific meanings in regards to things like constants, but the overwhelming majority of us all use IDEs now with autocomplete.
Personally, I prefer to use prefixes anyway to denote that info. Works better with segmenting stuff for autocomplete, and has less overhead of deriving non-explicit meaning from stuff like formatting or capitalization choices.
On top of that, you really shouldn’t be using variables with the same name but different capitalization in the same sections of code anyway. “Did I mean to use $AGE, $Age, or $age here?” God forbid someone come through to enforce standards or something and fuck that all up.