"The Eternal Mainframe" by Rudolf Winestock is some quality read.
Anyway. The point is that people moved away from mainframes because they wanted to be free. They didn't want to be shackled by IBM's by-the-minute CPU charges and other restrictions. They didn't want their destiny altered by anything other than their own free choices.
This is why “free” and open source software (FOSS) will not help us. A software license touches on the software, not on the human relationships which the software mediates. It is those relationships that lock us into positions where Zuckerberg's foot is on our necks. In fact, it's FOSS that has enabled the web companies to bootstrap their start-ups so quickly and cheaply. It's FOSS that gave those web companies the flexibility to insinuate themselves as gatekeepers over our personal data.
The desktop computer won't completely disappear. Instead, the outward form of the personal computer will be retained, but the function — and the design — will change to a terminal connected to the cloud (which is another word for server farm, which is another word for mainrack, which converges on mainframes, as previously prophesied). True standalone personal computers may return to their roots: toys for hobbyists.
Link: https://www.winestockwebdesign.com/Essays/Eternal_Mainframe.html