TCP/IP / packet-switched networks date from the early 1960s. Apple's first smart-tablet, the Newton, famously flopped. I remember seeing one at work in the early 1990s and saying "why would anyone want anything like that?" Given its capabilities, or more accurately, limitations, that was accurate.
IoT two decades ago was powering the first generation of pop-up ads as X10 home-automation systems. Blockchain is rebranded Merkel trees, dating to 1979.
Drones, as with most other aircraft-based technology, is a matter of lightweighting systems sufficiently, at a reasonable cost, to enable them to remain aloft. Even now, the popular copter-drones have only a few minutes of operating time. Further lightweighting, fixed-wing, fuel-based, or other changes are likely still required.
Self-driving cars are a problem of complex nature in which further enhancements to basic automation provide ever-increasing domains of application.
AR/VR suffers from human-machine interfaces. Simulator sickness (https://en.wikipedia.org/wiki/Simulator_sickness) affects professional pilots -- a device that makes a substantial portion of the population physically (and projectilely) ill will have limited uptake.
Neil Postman's Seven Questions remain highly relevant:
1. What is the problem that this new technology solves?
2. Whose problem is it?
3. What new problems do we create by solving this problem?
4. Which people and institutions will be most impacted by a technological solution?
5. What changes in language occur as the result of technological change?
6. Which shifts in economic and political power might result when this technology is adopted?
7. What alternative (and unintended) uses might be made of this technology?