Radio connected dumb terminals was easily achcievable back in the day, there was just no need for it.
Cloud is just dumb terminal or thin client rewritten with modern tech. It addresses issues on mobility (not an issue in the dumb terminal era : p ) and addresses exactly none of the the fundamental issues around near all of your data and functionality being held centrally by a third party. Two huge issues that were addressed by the PC, for sound business reasons, not technological ones.

Could the mobility seemingly offered by the cloud outweigh the issues around centralisation for some? Absolutely.

The marketing ploy, is trying to get people to discount them as a non-issue. Fish hook their customers with an investment it would be very difficult for an exec to write off.
So most Cloud boys are pressing the greed button with cost savings, then while the poor gonk is thinking of their upcoming bonus and promotion, trapping their nads in a vice.

You can fool some of the people all of the time...