I know you're probably being exaggerative in this statement but to add some clarity: COVID proved that most people's jobs are pointless (more or less), however, there's maybe like 10-15% of the workforce that if they didn't work, everything would come crumbling down and society would fall apart. Examples we saw during COVID: Medical staff (nurses, doctors, EMTs), truck drivers, train operators, agricultural workers, electricians & energy workers at power plants, waste management workers, construction workers, various retail employees (grocery store, pharmacies).

As to your point, humans with copious free time leads to civil unrest - so the fact that 80+% of people's jobs aren't critical to the functioning of the country is quite concerning - especially now with the recent advances in AI. Another concerning thing is that countries with high unemployment rates (20%+) typically have revolutions or similar. We've also never seen what 80% unemployment (or even 50%) looks like in a country not during a time of war or during a natural disaster. During those times extreme unemployment rates are seen as temporary by the population, whereas, with unemployment caused by AI - it won't be viewed as temporary so I think it'll spark a revolution pretty quickly because people won't see a light at the end of the tunnel and immediately call for change.