D/F is a fundamental tool of both approach and approach radar control, especially if you have a lot of VFR traffic. It is often the one that saves the day with alerting service/aircraft lost scenarios. We also used it on GMC to find out which a/c had the Tx button inadvertantly pressed.
We never used it on area, but our Distress and Diversion cells have comprehensive D/F coverage.
Ask yourself this:- Do the people who want to remove this kit hold any aviation licences?