More appropriately (since armor won't protect you from a two ton SUV), do you wear bright colors, reflective tape, and night-time illumination when walking?

The answer from any smart pedestrian certainly should be yes, but it's surprisingly hard to buy neon yellow jackets or hats. They're rare for bclists and almost nonexistent for mcyclists, of which I'm both.

Apparently most mcyclists would rather be cool than visible.

If I walked at 30km/h on the streets I would definitely wear one

The poster in another comment says he wears helmet and body protections when skying, I think it's just common sense and not wanting to suffer sever consequences for no real reason.

I used to wear an helmet when skating.

Why bikers think they are the only immortal beings on this planet?

I might if I walked in the street. I don't encounter a lot of cars driving on the sidewalk, and in theory I shouldn't encounter cyclists there either.