Very interesting, thanks! But it is a bit different than backing out of a support promise.
If Google backs out of the 10 years of updates promise, then people who bought a Chromebook right now wouldn't be getting what they paid for.
However, the Pixel Pass buyers all got what the paid for. The only thing they didn't get is the convenience of automatically buying a new device. But I'm not sure how that would have actually worked. Maybe it wouldn't have been that convenient after all.
Also, Google didn't explicitly promise to support Pixel Pass for any specific period of time. Some people might say "a new device every 2 years" means at least 2 years. But it's not explicit. And some people might interpret "a new device every 2 years" to mean it's supported for infinity. There's no end date stated.
If Google backs out of the 10 years of updates promise, then people who bought a Chromebook right now wouldn't be getting what they paid for.
However, the Pixel Pass buyers all got what the paid for. The only thing they didn't get is the convenience of automatically buying a new device. But I'm not sure how that would have actually worked. Maybe it wouldn't have been that convenient after all.
Also, Google didn't explicitly promise to support Pixel Pass for any specific period of time. Some people might say "a new device every 2 years" means at least 2 years. But it's not explicit. And some people might interpret "a new device every 2 years" to mean it's supported for infinity. There's no end date stated.