PowerShell is more like a worse Python and its core functionality is not the same as that of Unix shells.
PowerShell's commands ("cmdlets") are .NET classes within PowerShell, not arbitrary executables as in Unix shells. PowerShell's "object pipeline" is function chaining like in Ruby, not using OS-level pipelines as in Unix shells.
PowerShell is really just a .NET CLI, analogous to the Ruby's irb or Python's CLI, but dressed up to look like a Unix shell.
PowerShell's commands ("cmdlets") are .NET classes within PowerShell, not arbitrary executables as in Unix shells. PowerShell's "object pipeline" is function chaining like in Ruby, not using OS-level pipelines as in Unix shells.
PowerShell is really just a .NET CLI, analogous to the Ruby's irb or Python's CLI, but dressed up to look like a Unix shell.