Its not the same thing. You are comparing a live closed system (brake lights have live 12 volt wiring) to a open circuit that you can switch off at at least two points.
Where by "live 12 volt wiring", you mean "live 12 volt wiring, , but only 'live' when both the ignition and the brakes are on (or sometimes the tail-lights where they use dual-filament bulbs), which is suitably fused so it wont catch fire if you short it, and which is completely safe to touch unless you manage to pierce through your ribcage with two conductive spikes and connect opposite ends of the low-voltage supply directly onto your heart muscle", right?
Seriously, I'm trying to imagine any scenario where ham-fisted attempts to change a brake light bulb could result in anything more dangerous than a mild surprise and a blown fuse if you manage to short the contacts. You are, in my experience, _much_ more likely to injure yourself kicking the cat 'cause you end up so frustrated having to remove 47 easily breakable plastic clips holding the shitty carpet/trim in the trunk to get to the bulb - than being in any danger from a 12V electrical system, live or not.
And, as someone who lives where out wall outlets provide 220V AC, and who's taken more than his fair share of belts from not only 220V but also 415V three phase power, I find it vaguely amusing when people are deadly afraid of puny 110V electrical systems ;-)
I've had past clients partially burn their cars after chaging a light bulb. Keys off the ignitio and all. I talk out of experience. I've owned 3 repair shops. Seen worse things happen.
One of them was an electrical engineer believe it or not. He partially burned the wiring on his 911 Porsche when replacing a lightbulb. Its just crazy.
Was this _just_ a bulb replacement? Or was bulb replacement the last action is a chain of errors? I'm pretty sure I've never worked on a car that didn't have suitable fuses for light bulb circuits/wiring.
(Having said that, I have been personally responsible for screwing that up - "130W headlight globes, Sure! I'll just swap out the 15A headlight fuse for a 30A one! This wiring looks _fine…_" (So far as I know) I always got away with that, perhaps more out of luck and good engineering by the manufacturer, rather than having sufficient expertise to be able to make a correctly informed decision about whether the OEM loom was good for double the original current…)
Perhaps modern cars are build with significantly less margin-for-error than my experience dictates? My car-tweaking experience was mostly on late '60s / early '70s Volkswagon Beetles, and mid '70s Ford Escorts. I haven't owned a car since '95 (and the last one was a '72 SuperBug). I've been pretty much motorcycle-only since then.
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