nuclear+renewables is the best combo. I see we now have automated vehicles mining for materials at the sea floor, so this should lessen the carbon footprint you mentioned.
Thats why I think the pandemic sounded the death knell for the fossil fuel cartels, it was nature's way of fighting back against the virus that is humanity and its overpopulation of the planet which has destroyed the environment and resulted in a mass extinction event for most other species. We've reached a tipping point and once any species becomes too dominant, it goes bye bye or gets severely reduced- that's how the system is built to work. To "beat" this system and reach a new overhead, you'll eventually have to colonize space. Hence all the investment in space going on by billionaires.