Actually Android One devices are also guaranteed (inasmuch as the tiny text at the bottom of the Android One website [1] says) three years of security updates
> Monthly security updates to be supported for at least 3 years after initial phone release.
(scroll down to the bottom of the page and look for the double asterisks footnote. I don't know why they want to hide what is IMO the best reason to get an Android One device)
Good point. They previously removed this language from the website, glad they put it back. So yeah, buy an Android One at launch is good advice for the 3 years of security support.
It's still a short window IMHO, and it's bad for the planet to throw working devices after 3 years.
> Monthly security updates to be supported for at least 3 years after initial phone release.
(scroll down to the bottom of the page and look for the double asterisks footnote. I don't know why they want to hide what is IMO the best reason to get an Android One device)
[1]: https://www.android.com/one/