I've never been comfortable with 'just-in-time' anything. I'd much rather have a more robust system with spare capacity built in. The question is how much spare capacity and at what additional cost. The costs now being faced to deal with the energy price explosion will, I guess, exceed the savings made over the past few years by 'clever' beancounters trimming, trimming, trimming.
Short-sightedness seems to be the new national condition. It'll be alright on the night.
I would say water for drinking and energy for heating in winter are essential supplies which should never fail.* We are not a third world country with massive debt problems preventing investment in infrastructure (yet).
*Incidents will occur and there should be contingencies in place - water tankers, bottled supplies, duplicate routes for power lines, mobile substations etc.