That's inexcusable, and this attitude carried over to security updates is a big reason some corporates left Samsung and went to Apple -- e.g. the A5, a midrange phone comparable with the iPhone SE, lost access to updates when the device was perfectly usable.
Samsung must've felt the feedback, because this year they announced a formal policy on security updates -- too late for the S9, but customers from S10 onwards ought to benefit[1]. They've been a lot better with Android updates on newer phones too -- Project Treble probably played a role.
> Galaxy devices will now receive regular security updates for a minimum of four years after the initial phone release. By extending support for security updates delivered on a monthly, quarterly or biannual basis
[1] https://news.samsung.com/global/samsung-takes-galaxy-securit...