Tested: Windows 11 Pro + PowerShell 7.5.4 (run terminal as Administrator).
One-shot removal
# Lists current exclusions (optional)
Get-MpPreference | Select-Object ExclusionPath,ExclusionProcess,ExclusionExtension,ExclusionIpAddress
# Remove everything
$mp = Get-MpPreference
$mp.ExclusionPath | ForEach-Object { Remove-MpPreference -ExclusionPath $_ }
$mp.ExclusionProcess | ForEach-Object { Remove-MpPreference -ExclusionProcess $_ }
$mp.ExclusionExtension | ForEach-Object { Remove-MpPreference -ExclusionExtension $_ }
$mp.ExclusionIpAddress | ForEach-Object { Remove-MpPreference -ExclusionIpAddress $_ }
# Verify (all should be empty)
Get-MpPreference | Select-Object ExclusionPath,ExclusionProcess,ExclusionExtension,ExclusionIpAddress
About the red errors
If you see:
Remove-MpPreference: Cannot validate argument ... The argument is null or empty.
it just means that list (e.g., ExclusionExtension or ExclusionIpAddress) was already empty. You can ignore it, the other lists are still removed.