Oil going through Hormuz is 20%, not 80% of global supply. It's true that demand is pretty inelastic, but it's not like it can't be cut at all.
During the 1973–74 Arab oil embargo, the disruption removed approximately 4.5 million barrels per day (mb/d) from the market, which constituted about 7% of the global oil supply at the time. This disruption significantly impacted global supplies.
20% is a lot more than 7%. This could be worse than 1973-74. As a 10year-old in 1973 I remember spending a lot of time in the backseat of the station wagon as we were waiting line line for gas.
For context, during the first COVID spring (March-June 2020) oil demand fell by 20%. Because nobody was driving or flying anywhere. That's what it took to cut 20%.
That's completely incorrect.
Covid demonstrated that. We have optimized so strongly for profit (outsource everything, just in time inventory, etc.) that we have no robustness in the face of disruption. There are now single chokepoints everywhere.
Yes, we could retool. But nobody will retool without a check from somebody. Everybody will simply hold their breath waiting for the crisis to pass. Everybody held their breath for Covid; they will absolutely do so with the knowledge that the orange clown will disappear in two years.