I don't see a use case for these cameras. Phone takes amazing pictures and videos and is always on hand and if I need something more polished, I just get DSLR. Sure DSLR is more expensive, but if I want to do something well, I'd rather go all in.
Who is mounting a DSLR on bike, helmet, chest? Taking it in the ocean, etc.
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.