It's not necessarily about the jobs, it has more to do with the economic engine. The economic engine has been in a virtuous feedback loop for hundreds of years

It's not necessarily about the jobs, it has more to do with the economic engine. The economic engine has been in a virtuous feedback loop for hundreds of years. People are born, get educated, find work, and become consumers and savers, thus generating the sales companies need to innovate and lending the capital for others to start new ventures. Step by step we've built this whole engine simply because we were born in this system. If jobs are lost fast enough, the whole engine shuts down: as AI replaces jobs faster than new economic sectors are created levels of spending in society will decrease, leading to reduced profits (or increased losses) and increased layoffs, thus speeding up the process. The thing is that AI has the potential to replace all jobs any human could ever have. Now, your second point regarding jobs that can't be replaced: every job can be replaced. The human brain isn't special it's just a machine. And you're looking at AI research in a linear fashion. At some point enough computational power breaks through any problem.