The thing is, we've already been there and done that. You think you have choices, but you won't for long. We're all boiling one degree at a time.
> You can still buy appliances with no internet connections at all, or buy open hardware and run open source software.
Maybe, if you know what to look for. Most consumers don't. They'll buy a Dell and not realize Computrace exists. I work in the field and I don't even know a fraction of what I don't know. I'm just one asshole defending against legions of better-paid actors with an infinite capacity for insidiousness.
Just wait until some well-meaning, progressive state like California decides to legislate that all houses must be smart-conforming. All aspects of your house will have a network interface whether you like it or not. How many homeowners are capable of setting up VLANs for their lightbulbs? How many homeowners are going to deconstruct every (networked by default!) smart-item they purchase and check for motion sensors, cameras and microphones? The NSA backdoored smart TVs already. Huawei backdoored routers, and Blu sends god-knows-what to China in the background. It's happening.
In this day and age, you may as well assume every product that comes out of Silicon Valley is a glorified exfiltration agent. If you give anything a network interface, by god it's going to use it to report something, and you don't know that it's happening or what's being communicated. You-have-no-control.
Given the recent interest in mesh networking I expect that to become a new vector-- install enough Huawei appliances in an area (give them away for free, or undercut competing vendors), each serving as a wireless mesh node, and you only need one internet-facing node (like a Huawei cellphone or router) in that mesh to be able to command and control any of the devices or peripherals around it. If anybody questions why a digital pictureframe is emitting wireless signals, it's for the discovery service, of course. It has to get updated weather information from somewhere, right? Consumers will accept that. And thus you invite a decentralized botnet into your home.
> Surely inexpensive and/or used cars will dispense with GPS and other high tech features; in addition, I wouldn't be surprised if (should this become a regular problem) a modding community develops around car ownership (ownership in the sense of right-to-modify).
Used cars will, until that pool dries up, yes. How many cars can you find that still use carburetors in favor of ECU-controlled fuel injectors?
We lost the right-to-modify battle the day ECUs became standard in all cars, inexpensive or not. Without proprietary knowledge, you can dink around with the oil and tires, but you can't fundamentally change how the car works. You can't even change the brake fluid on some cars without a proprietary command telling the pump to expel it. The war for right-to-modify will be lost when we're all driving Teslas (or John Deeres).
You can hack it, sure, about as competently as you can hack a PS4 or iPhone. The day will inevitably come where you want to use a particular app or service you paid a premium for (like warranty repairs, autopilot, PS Online or iTunes) and they'll tell you to pound sand unless you install their factory-certified firmware that opts-in to tracking. Or new games/features will simply refuse to work on your hacked firmware. You will be left in the dust.
That also assumes your insurer doesn't find out you tampered with an otherwise autonomous car, potentially impacting its safety features by refusing OTA updates and putting you in a higher risk pool. They may decline to insure you altogether.
There are consequences for not complying with progress; you yourself mention one of them. I'm disappointed you think it's hyperbole-- this attitude is why things have degraded to the current state of affairs.