> If we could guarantee that on every moral issue on which there is currently widespread agreement
This is ridiculous to me and all you need to do is get a group of friends to honestly answer 10 trolley problems for you to see it like that also. It gets fragmented VERY quickly.
It may be relatively achievable to get 10 'friends' into ethical alignment via helping them all develop a deeper perspective on philosophy in general and a particular, finite set of ethical questions specifically.
Doing this with thousands of people - let alone hundreds of millions - eventually becomes statistically impossible. There is a hard cap defined by energy requirements somewhere for any given system. Large scale ethical alignment is simply not a solvable problem in our current situation.
This is ridiculous to me and all you need to do is get a group of friends to honestly answer 10 trolley problems for you to see it like that also. It gets fragmented VERY quickly.