Removing duplicate audio files with different UTC timestamps in filenames, using PowerShell 5
While -Filter is usually the fastest way as it handled by the provider,
I'm not sure this is true compared to one -Include with an array which only recurses once instead of 8 times.

$Include = '*.clip*','*.ptf','*.wfm','*.repeaks','*.DS_STORE','._.*','Thumbs*.db','*.ini'

Get-ChildItem  -Recurse -Name -Include $Include | Remove-Item


As for the duplicates, your approach will only eliminate dupes in the same folder.
An alternative would be grouping the output with a calculated property which strips off the date in parentheses. And then iterating the groups and sorting by whatever means, keeping only the first/last - removing the others.