Exactly.

The head lights draw enough amperage through the small wires Ford used that is causes the switch and connector to get hot.

That in turn melts the bottom of the switch which also is generating heat in the dash light dimmer rheostat.

So if you get the head light load off of the switch, much less heat generated, so the switch will last forever.

If you tow a trailer or have added more marker lights to your truck, that load is also added to the headlight load.

When I did my relay mod, I also used a relay for the marker/parking lights so the trailers I pull don't overheat the switch either.