If the AI boosters are right about what the technology will be capable of in 5 years, at least some of the big player’s investments will be literally the most profitable investments that ever happened. This is a potential mispricing, not a system inherently incapable of paying off long term like the subprime mortgages were. I don’t think another step-change like we saw with GPT2/3 is likely in the mid-term future, but I don't think anyone has shown it’s virtually impossible.
That's betting, basically, that there will be an oligarchy (multiple dictatorship) and the oligarchs (dictators) will be whoever owns OpenAI shares.
If AI turns the world into a dictatorship, what gives anyone the idea they'll just agree to share that dictatorship with their shareholders? They could just ignore company law - they're dictators!