> There is, however, a completely different vision for how web infrastructure should be and that is to have extremely resilient hardware and simple software.

You actually need both, the point of the extremely resilient hardware is that it can act as the single source of truth when you need it - including perhaps hosting some web-based transactions that directly affect your single source of truth. (Calling this a "model" for web-based infrastructure in general would be misleading though: a credit card transaction on the web is not your ordinary website! The web is just an implementation technology here.) Everything else can be ephemeral open systems, which is orders-of-magnitude cheaper.