I think 3 is flawed in general, since 5% price increase often does not result in 5% salary increase. Wages have not kept up with inflation/CoL especially at the bottom, for decades. Instead, consumption would probably drop, especially for non-essentials. If consumption is low, prices would also probably remain low, or possibly lower, especially for non-essentials. For high-demand essentials, probably supply/demand is more likely to create higher costs, than inflationary sources.
Right now I think a lot of people are in hunker-down mode. Without outrageous consumption to increase demand, reduce supply, raising prices and CoL to force increased salary demands, I don't think this self-fulfilling inflation will happen.
Maybe the danger is people being overly-flush with cash after COVID-19 passes, but that looks like it'll be pretty far down the road, and I think we're also due for a bubble to pop on Wall Street, which will probably also hamper inflation.