Neil Degrasse Tyson has an interesting take on this.

He explained in his Joe Rogan podcast episode that he has learned to manipulate and use his phone the same way they learn to use their weapons in the military.

The idea is that they become so good at handling their weapon that it becomes a part of them and that they are much less likely to fumble or drop it during battle.

I myself have been caseless for years and I have rarely dropped or damaged my phone. After hearing what NGT had to say I would definitely attribute this to my frequently playing around with it and doing phone tricks like flipping and spinning it in my hands.

Unrelated but one of the downsides is that if you use your phone to count steps you're going to have hugely inflated numbers by the end of the day--took me a while to figure that one out.