Yes, the stackexchange (implicit) model contributes to this. It assumes once a Q has been asked and answered, the issue is resolved. Due to the non-duplicates policy, any corrections or updates are supposed to be added to the same thread. But the original accepted answer will have a tick mark next to it and likely a high score. So naive users don't read further and the obsolete answers remain heeded.

Some sort of deprecation or salience decay needs to be added.