At present, connecting your device is an opt-in since you have to give it wifi creds. In the future, devices will be connected by default and you'll have to opt out if you want to disconnect. Even if you're one of the few people who opt out, devices are going to have fine print that they can always receive "critical" updates via mesh.
Eventually many devices simply assume they are always connected, it's baked into their operation. They'll delegate key features to the cloud and opt-out won't even make sense.
And that won't work easily, or for too long. They will just embed stuff in chips.
Maybe we will see "Brazil" style setups with TV's in some sort of Faraday Cage
The answer is not giving these companies money.
I’ve had to do it myself once as well.
I don’t care about voiding my warranty.
Second best, though, is getting out the soldering iron.