I’m curious… Did you experience different behaviours with other devices?
I assume you have enabled “Show all notification content” in Settings/…Lock screen/Privacy? With this setting I see exactly the same notification content whether locked or unlocked.
Which raises the question of how exactly you define a “notification”… To my mind a notification will be a summary alert containing brief information (App name, subject, sender (if messaging app) , and yes, first line of the message itself). Tapping the notification should bring you to the in-app message or alert in full, and in my opinion, to be able to do so without any authentication would be a security vulnerability in my opinion.
So in short, I think the feature is behaving as expected if the expectation is that “all notification content” is not the same as full app message/alert content etc.
