Many things can save your life. Most of them don’t have a UL-provided monopoly making it quite unpleasant for anyone to compete to produce the version that fits where you need it.
A 1-pole GFCI breaker, a 2-pole GFCI breaker, and an ordinary GFCI outlet all have the same clever pair of coils, the same IC, and rather similar trip mechanisms. Yet the costs are quite different, and the costs get _really_ absurd if you want a breaker that trips at a level other than ~5mA.
And yes, they’re all very much worth using. I do wish that electrical codes would at least start encouraging the use of GFCIs for 240V outlets, which might encourage manufacturers to start making them, and those would actually be able to compete with each other.
