In my opinion the "store everything" approach is actually a good thing. By not caring about which pictures look best I can immerse myself in the moment more instead of caring about storage. Many times when I reviewed pictures I took in the past, shots I thought were terrible actually captured details that the "good" shots didn't. You'll have more clarity when leisurely reviewing pictures on a computer.
I agree that storing pictures on someone else's service is not a good idea in the long run. The recent AI hype wave affected RAM, SSD and HDD prices. I think grabbing large SD cards now before they are affected too would be a good move.
There are batteries, recent advances have resulted in cheaper batteries that can store more power.
Alternatively the energy can be used to create hydrogen and that can be transported.