I have a chromebook from 5+ years ago other than the 4gb of ram I don't see why Google couldn't just keep updates going forever? Surly chromeOS isn't so "heavy

I have a chromebook from 5+ years ago other than the 4gb of ram I don't see why Google couldn't just keep updates going forever? Surly chromeOS isn't so "heavy" now that it cannot run on a 3.5gz dual core and 4gb of ram? Latest of any major distribution still runs pretty well.