Page Filter - disable the selection for "All"

Hello all

I have created a page filter with several countries. The users should select a single value depending on their location.
Is there a way to disable the selection "All"? In this case it doesn't make sense to show all locations at the same time.
I tried to set the filter like shown in the following image but still it shows the selection "All" (top left in the background).

Thanks a lot and best regards

Stefan