So I'm guessing that we somewhat agree that straps are like lifting belts, we only need them, when we need them. As the last few reps on max loads.
I do find that after using straps on lifts, my grip does catch up after awhile. Static holds, for 10-15 seconds are a fine way to increase gripping strength, I have found. As are hanging from a chinning bar with extra weight attached, for 10-15 seconds and with a false grip (thumbs over the bar). Good luck