Believe me, I feel your pain, as this sort of thing has happened to most of us at one time or another.
One of the great strengths of the Android platform, though, is the plethora of alternative apps and, in fact, alternative custom ROMs for these devices if one is willing to root them and install a custom recovery. One need not stick with the default messaging app, that's for sure. I would not be holding my breath for the return of the feature that's been removed from contacts any time in the near future.
When it comes right down to it, though, I count myself very lucky that Samsung/T-Mobile continue to push out major Android version updates for the Galaxy S7. As Android is progressing security is becoming a far more significant concern, and Android 8.0/Oreo is a major step forward in that realm.