About style
Style in the context of a scripting language is all about aesthetics; it describes how variables are named, how code is indented, where opening and closing brackets are placed, and so on. Style is an easy thing to disagree with; the topic is full of opinions, many of which come down to what an individual feels is right.
PowerShell does not have an official style, nor does it have an official best practice.
PowerShell does have a set of guidelines for cmdlet development (commands typically written in a compiled language like C#): https://learn.microsoft.com/powershell/scripting/developer/cmdlet/cmdlet-development-guidelines.
It has been left to the community of PowerShell users and developers to provide further guidance. The community-created PowerShell Practice and Style repository describes many of the most widely accepted conventions: https://github.com/poshcode/powershellpracticeandstyle.
Many of these conventions (for example, warnings about the use...
