Are you willing to pay for the true cost of maintaining these devices for ~50 years? The original price might have been 600 USD. I think the answer is regulation. Another idea: Sell the IP to a separate company who will support the legacy product for a fee. The original product will tell you how many years support is included (not lifetime). Later, there may be monthly charges. I doubt you will like that idea, but it is more honest. Germany has similar rules about car parts. Car manufs are required to make replacement parts available for X years after a car is manuf'd.
> Are you willing to pay for the true cost of maintaining these devices for ~50 years?
Sounds like Nest/Google didn’t think about that when they priced their products. That’s not the consumer’s fault. I’ve been de-Google-ing myself over the past couple of years and this is the final nail in the coffin. They could have given a partial refund, instead they insult customers with a “discount”.
How much do you think a server for config files costs? The true cost is very little here. You can make a server host a million thermostat connections for less than a thousand dollars per year. But let's 10x that to be safe, and have a sysadmin dedicate an overkill 1 day per week to keeping the servers happy. And we'll say the sysadmin makes well over median salary and costs $200k to employ.
For 2 million devices, that's $20k a year in server costs and $40k a year in sysadmin. For 50 years, that's 3 million dollars. So it would take a whole... dollar and a half per purchase to fund 50 years of servers.
Making this subscription-based would be fine, as long as I have my choice of providers. Because then I can run it myself on a raspberry pi or pay a big host a few dollars a year to handle my entire household of devices.
