Disables "Include inheritable permissions from this object's parent" to a given folder

Acl-RemoveInheritablePermissions.ps1

<#
.Synopsis
    Recursively updates the version of AssemblyInfo.cs files
.Parameter baseDir
    The root directory from which to recursively search for AssemblyInfo files
    Defaults to the directory of the script.
.Link
    https://gist.github.com/z0c
#>

param(
    [Parameter(Position=0)] [string] $path = $(throw "missing -path param"),
    [Parameter(Position=2)] [string] $allowed = ''
)
    
$ErrorActionPreference = "stop"
$allowedUsers = @()
foreach ($u in $allowed.Split(',')) {
    if ($u.Contains('\')) {
        $allowedUsers += $u.ToLowerInvariant()
    }
    else {
        $allowedUsers += ($env:computername + "\" + $u).ToLowerInvariant()
    }
}

$acl = Get-Item $path | Get-Acl
$modified = $false
$acl.Access | ? { 
    $allowedUsers -notcontains $_.IdentityReference.ToString().ToLowerInvariant()
} | % { 
    Write-Output "Removing access right of user " + $_.IdentityReference
    $acl.RemoveAccessRule($_) | out-null
    $modified = $true
}
if ($modified) {
    $acl | Set-Acl
}

# Disable permission inheritance from parent object
$acl = Get-Item $path | Get-Acl
if (!$acl.AreAccessRulesProtected) {
    $acl.SetAccessRuleProtection($true,$false) 
    $acl | Set-Acl
    Write-Output "Disabled inheritable permissions"
}
else {
    Write-Output "Inheritable permissions already disabled"
}