Yes and I have given this a lot of thought.
But I always come back to the fack that I should be able to merge 3 RAW images and then have one RAW image to work with. I know I can open as a smart object but it isnt the same.
The issue is once merged, the exported 16bit tiff doesnt have the recovery that the RAW does. I would manually mask and combine, but real estate photography requires quick turn around. Sometimes I have 3 properties in one day.