There's potential for a huge gain in efficiency here. The stock market is fundamentally a long bet (if you want to short the entire market you invest in things outside it). Of course the market is exited at the long term prospects of that.
Also, you're being a little disingenuous when yo say "These are the same markets that cheer when job cuts and redundancies are announced." When one under-performing company cuts jobs it tends to go up because costs are decreased. When a well performing company announces a mass layoff it tends to be a toss up because signals are mixed. When a ton of companies announce layoffs the market tanks because the signal being sent is things are getting worse all around. You're comparing a positive reaction to a single entity event (company announces layoffs) to a positive reaction for a market wide event (potential for covid to become less of a burden on the economy as a whole). You can't cross compare as if they're 1:1 like that.