Replace a significant portion of the workforce reliably (IMHO). And if that happens, I wonder what's next. I mean, if we automate say 30% of jobs these people won't be employable anymore without a drastic change in their careers' trajectories (I mean, they have been automated out of work once, any company would eventually do the same).
When that happens they will end up overcrowding other jobs sectors pushing salaries down for people already in these fields. Once that happens, the lost of purchase power will hit every sector and drag down economies anyway.
So, if I have to summarize my thoughts, we are either in a bubble that will pop and drag down AI related stocks, or it is not a bubble because the tech will actually deliver on what CEOs are touting and there will be high unemployment/lower salaries for many which in turn will mess up other parts of the economy.
Happy to be wrong, but given the hype on AI the winning conditions have to be similarly high, and millions losing their jobs will for sure have huge repercussions.