That is a difficult topic. Google did take steps to mitigate issues there. Android got Hardware Abstraction Layer to prevent blobs from blocking updates ; also, a lot of updates were moved from AOSP to the Play Service, so Google can more easily roll them out. (And to make AOSP and 3rd party roms less of a threat, eh.)
Edit : that said, most android phones have woefully short support period.
I have an S23, it’s definitely not every month. Last update package is currently dated 1st of may.