I can only speak for the US, but our electric grids and production are supposed to be air gapped for critical infrastructure. Healthcare? I doubt it based on the continuous leaks there - and medical supply chains are tightly integrated with internet/cloud… Shopping still has a fairly sizeable local accessibility for staple items, certainly food distro where the internet wouldn’t matter for at least a short while, but it’s also tightly integrated for Supply Chain Management, much like Health care - so there could be a run on it.
I’m not sure on public transport, but most are goverment led, so probably air gapped.
There’s also a shitton of dark fiber laying about. Internet infrastructure COULD be brought back up depending on the damage that triggered outages in the first place.
I’m not exactly standing behind it - just saying what I’ve read. I’m confident nuclear plants are after 9/11. Anything else is probably hit or miss, including petro/gas pipelines, coal, and generating plants specifically. Plus if a bad actor (likely state sanctioned) decides to, they can get through air gaps with spies/traitors/unwitting idiots with a simple USB drive. After air gapped uranium processing centrifuges were wrecked with an errant USB drive, I would expect all systems to disable or remove USB drive connectivity, but I’m sure that’s inconsistent… at best.