It’s only on max range flights that I throttle back as my airplane gets lighter. On typical flights, I instead take the 3-4% speed increase as the fuel burns off.

Lightness is a hugely important feature in airplanes. I’m not sure that current battery tech is poised to deliver on lighter aircraft for a given mission range. An additional drag (pun intended) for electrics is that landing weight is the same as takeoff weight except for skydiving ops.