Thank you very much for this thoughtful response, the interesting articles you provided, and the clear-up of the ETH/ETC confusion — I genuinely missed this bit.
I think we see eye-to-eye on a lot of things. I simply see a lot of those from the perspective of an IT professional with some experience in distributed computing. I regard sharding with some skepticism, because it is difficult to shard without, at the same time, making the shard proportionally cheaper to attack.
But I also fail to see the need for public chains. The only scenario where it would make sense versus permissioned chains, at least the only one I can see, is a post-apocalyptic everyone-for-themselves world with no institutions — firms, foundations, whatever — of public trust. Not only I don’t believe that this future is desirable, I believe that it realistically can not happen without also wiping out out technology like server farms and the internet in the process, rendering DLT useless.
I still need to do some research in regards to the private blockchains before I am ready to write more definitively on that subject.