I caught Cim Johansson say something that resonated well with what I have found.
There are different types of grip. Each one is pretty specific but adding any grip work regularly is like actually training with barbells for the first time. You may notice a little extra specific grip work has carryover to different grips and hand positions. And that itself will have carryover to other compound movements involving the grip.
Personally I think dead hangs from a bar are a very economical way to add some extra grip work and especially one arm hangs. Grip tends to respond to linear programming like everything else. I have an exercise or couple for training the extensors as well that you can progressively overload too and they're important for balance but I'd be lying if I said I trained finger extension regularly.
Wrists are awesome too and since handbone connects to wristbone it pays to understand the anatomy.