It’s very much “the gift we want to be the viral gift this year”. I searched on Amazon for flashlights this year, and the first three pages were all variations on this thing. And the croc flashlights are proof that we live in hell.
Anytime you need to use your hands but still need to see what you're doing. I can think of dozens of times I've needed a light to work on something with both hands in a badly lit area but didn't have someone to hold the flashlight.
That said, I'd probably want the battery pack somewhere else because I could see that being an issue hooking on things, especially in tight spots.
I totally see it but I feel like the same spaces where you need more light to see your hands and can't use a light are those where you can't fit extra stuff in with your fingers, if you get my thought.
My boss got me one for working inside control cabinets. As you usually have to have to power cut when poking around in a cabinet, lighting has to be supplied externally.
They could theoretically be decent for some car work where the body of the car shades everything.
They're better in idea than reality. 6/10
Also think of them as a supplement to a headlamp. Since your hands frequently shade what you're actually touching, these help supplement light right on the region of a hand shadow.
I could think of a million use cases just for a flexible flashlight alone. Every engine bay on modern cars is jam packed with shit or the space has been cleared for a crumple zone.