I have a Samsung Galaxy J1 (2016) that runs Android 5 and was (I later realised) already out of manufacturer support when I bought it new at retail in April 2018. That’s insane.
It’s as if Samsung was selling dishwashers and Apple was selling entry into an ecosystem.
Glad that this behavior from Sams is changing. I have S10, that were on Android 9, now it's updated to 11. I guess there will be no major releases, but I still will and do get now security updates for a few years. At least there is now predictable pattern on device support.