Yes. You do not want to use aperture or shutter priority if you want a constant exposure. If the drone/camera is tasked with keeping a set exposure, it has to change something in the exposure triangle to maintain that when conditions change (Shutter, Aperture, or ISO). When shooting video, you don't want any of those things changing if you want smooth, consistent footage, so you should always use full manual mode for best results. For photos, Aperture priority is great.
Also, on a 1" sensor, depth of field is so enormous that it almost doesn't matter. Add to that the fact that most drone shots are from high up in the air, DOF is practically infinite anyway. F2.8 on a 1" sensor has the same visual DOF as F8 on a full frame camera to give you some perspective - pretty much everything will still be on focus at any normal distance. This is also the same reason why your smartphone always has everything in focus even at F1.8 - the sensor is so tiny (1.2.3") that F1.8 has a DOF equivalent of around F10 on a full frame camera for comparison - so again, everything is pretty much always in focus.
