They essentially can. The A7RIII and RX100M6 can both shoot RAW to their buffers at 24fps then write it out. A full bracket usually takes less than a second and works just fine handheld.

> Shooting HDR quickly has the benefit that while you want something to reduce rotational shake, you don't need to be much longer in the position than the exposure time itself dictates. You can use the time you need to move to a new angle/direction to compress and store the RAWs, as barely anyone has hardware capable of yanking the camera to a new angle in a few milliseconds, just alone due to the power density needed to have something able to do this compact enough for casual handling. Imagine it like a much, much faster clockwork, with the purpose to deliver dozens of kilowatts for a few milliseconds to accelerate the camera and slow it right back down. Almost no one has such a thing that would keep the device steady during the exposure, but permit very short spacing between exposures that change the direction it is pointing by more than 20% FOV. If you were to rotate the camera that fast at over 50fps, good luck with the light you need (hint: your lens can't provide DOF at the aperture you need to do this even in full sunlight (sunny 16 rule)).

I'm not sure what you're getting at here. It sounds like maybe you're after some kind of automtaed panorama bracketing or something?