Would you want a killswitch for the fingerprint scanner PinePhone is developing?

PinePhone is currently prototyping a fingerprint scanner that goes on the back of the phone. I'm just curious, how important would a dedicated killswitch be for you?

Also, a bit of a tangent, but how do you feel about the fact that the killswitches are hidden behind the back cover instead of easily reachable on the side like the Librem?