Google details a list of Chromebooks and their support end-date in a single list [0]. I randomly picked a couple with support ending this year and it seems like a decent chunk of the devices being EOLed in 2020 were released in ~2015. ~5 years of support for a <$300 laptop is pretty good IMO.<p>[0]: <a href="https://support.google.com/chrome/a/answer/6220366#Acer&AOpen&Asus&Bobicus&CTL&Dell&EduGear&Edxis&Google&Haier&HEXA&Hisense&HP&Lava&Lenovo&LG&M_and_A&Mustek&Medion&Multilaser&NEC&Nexian&NComputing&PCMerge&Poin2&Positivo&Promethean&Prowise&Samsung&Sector_5&Senkatel&SMART&Toshiba&Viewsonic&Viglen" rel="nofollow">https://support.google.com/chrome/a/answer/6220366#Acer&AOpe...</a>
Or Google could just provide long term software updates for their hardware like Apple does. Just because the browser portions continue to be updated sounds like the other portions won’t be.