PowerShell Delete AD Accounts in local machine

I am planning to delete all local ad user accounts on the machine which are not built-in accounts or the IT support AD account called “SystemAdmin”. However, my every attempt to do this always ends the same way, I can only get my power-shell script to list out all the local user accounts and not any of the active directory accounts logged into the machine. Some assistance would be appreciative.
Here’s a snippet of my script:

$localUsers = Get-WmiObject -Class Win32_UserAccount -Filter "LocalAccount='True'" | Select-Object -ExpandProperty Name
foreach ($localUser in $localUsers){
  if (($localUser -eq "ITSMELSS") -or ($localUser -eq "Administrator") -or ($localUser -eq "defaultuser0") -or ($localUser -eq "Default Profile") -or ($localUser -eq "DefaultAccount") -or ($localUser -eq "Guest") -or ($localUser -eq "WDAGUtilityAccount")) {
  Write-Host "Keeping:"$localUser
  }else {
  Write-Host "Deleting:"$localUser
  #Remove-LocalUser -userName $localUser

The use case for this script is for ‘cleansing’ loan computers of their user accounts after they’ve been returned which do not require a full re-imaging.