When you want to film your kid jumping into a pool (from inside the pool), do you do it with your phone or with your DSLR?

The use case is niche but there. I ride mountain bikes and off-road motorcycles and have a GoPro on my helmet. A phone is the wrong form factor and a DSLR is too heavy.

Same with surfers, or people who race cars etc. Having a physically small camera, with robust mounting and stabilization is not something a phone in a gimbal or a "real camera" can provide.

Who is mounting a DSLR on bike, helmet, chest? Taking it in the ocean, etc.