AA much hate this might be getting, they're offering discounts on a new product, and 16 years is a hell of a lifetime. Imagine having to support software written in c99 maybe even c89, with some homebrew UI full of bugs.
I understand you may be from a field where supporting software from the 70s is required, however someone is probably paying big bucks for that software as well. Replacing the software you work on might cost millions, replacing a thermostat costs 300 usd.
I would love to live in a world where software support lasts 70 years. But consumers don't look at software support, so it's not budgeted in the price, and thus doesn't happen in the consumer space. Getting 16 years in a consumer device is long.
In the field you're working, stability, longevity, and robustenes is probably a requirement, not a nice to have.
Think about it like this: Even if the average home nowadays had only about 10 such devices (I am quite sure the average home has a lot more), that are needed for kitchen appliances, heating, warm water, window shutters, solar panels, etc to function - that means on average about once a year one of the essential functions in the house stops working unless you replace a part. Not because it's broken, but because "SW support is discontinued". Seriously, I want to smash everyones faces for those "early adopters" who think smart homes are great, and of course the companies who put software in every little component.