You will always be able to do general purpose computing, maybe just with a loss of speed. No one is going to back door every 10 dollar microcontroller.
10 dollar microcontrollers are way more powerful then pen and paper. In 10 years they may be as powerful as today's $2000 computers.
It's a matter of scale. You can do general electronics with some AA batteries. If you want to build a nuclear reactor, yeah there will be interest from others in your affairs.
"In 10 years they may be as powerful as today's $2000 computers."
That's been continuously true for some decades now. What might save us is capitalism in that the bean counters are not permitting $10 controllers for a toaster, those get the ten cent controllers. Also the cost of labor to program those is a limiter in that a mass market toaster with $50M of programming budget will be financially destroyed in the marketplace by a competitor spending $5K on "its a 60-180 second timer, nothing more".
An embedded swamp will form of $25K cars with expensive insecure software. Your car will get powned 1000x more often than your toaster even though the risk to your life is fairly similar.
