Why not? An incandescent backlight _physically gets hot_, I'd argue that has even less place in this application. It's just what they had at the time.
But in either case, it's perfectly safe. There's no way to touch either the hot parts or the high-voltage parts. And even if there was, the battery doesn't have enough oomph to do anything more than tingle once the prickly part was trying to drive something as massive as a fingertip.
I noticed the noise too, when I owned one, but I figure silencing it would've cost size, weight, and power. And the noise was never more than a curiosity, so I'll take it!
They aren't talking a out safety, they're talking about efficiency and accuracy. A boost converter is inefficient and you don't have power to waste like that in a watch. And electrical noise perturbs the timekeeping parts.
However your comparison to incandescent and your point about the momentary nature are both valid I'd say. If they had magic, they'd have used it. So they took something fundamentally inefficient and added engineering to make the best of it. A bad thing, done as well as possible,
You could say almost the same things about incandescent. It's not electrically noisy, but temperature sure does perturb the timekeeping, and incandescent definitely wastes power. Especially if you need the filament to last indefinitely instead of replacing it easily.
But in either case, it's perfectly safe. There's no way to touch either the hot parts or the high-voltage parts. And even if there was, the battery doesn't have enough oomph to do anything more than tingle once the prickly part was trying to drive something as massive as a fingertip.
I noticed the noise too, when I owned one, but I figure silencing it would've cost size, weight, and power. And the noise was never more than a curiosity, so I'll take it!