I had a Windows 2012 R2 printserver where a WSD port was still there after printer deletion. Delete only the port was not possible (operation not permit).
The spooler will delete the port only if it is assigned to a printer and you are deleting the printer. As workaround you can create a fake printer using this port and a preinstalled driver, then delete the printer.
But using powershell is possible to work less…
List all the WSD Printer Port:
Get-PrinterPort -Name wsd*
Delete the WSD Printer Port (PortName):
Remove-PrinterPort -Name PortName
or if you have only one WSD port:
Remove-PrinterPort -Name (Get-PrinterPort -Name wsd*).name