Centralised "economies of scale" mean consolidating risks into geographical and corporate ownership. I mean look at the current situation: that consolidation means there are a few corporate players, any of whom could just pull the plug on a huge amount of infrastructure in a war or other geopolitical mess.

Also we have a layer of abstraction above the datacentre now which is the cloud provider. And that does not necessarily (especially in our case) have an economic advantage. And it is again a single point of failure. One cloud provider compromise and the scope of compromise is across multiple datacentres and businesses and potentially national governments.

I'm suggesting bringing a lot of stuff back in house or within tens of thousands of small datacentres where there's a few racks max. And we keep our abstraction depth low.

I'd go as far as designing things to be permanently disconnected or just occasionally connected these days. Even single-user stuff reaches into clouds and datacentres when it doesn't need to.