Do you have proof? My Note 20 Ultra (released in 2020) received 3 updates in the past 35 days -- and this is for a region that's trailing Europe and the US in terms of updates.
https://9to5google.com/2021/04/05/samsung-drops-galaxy-s9-do...
https://r2.community.samsung.com/t5/Galaxy-Note/Samsung-Gala...
S9: https://doc.samsungmobile.com/SM-G9600/TGY/doc.html
Note 9: https://doc.samsungmobile.com/SM-N9600/TGY/doc.html
You can see they still received updates this month.