Finland here, third gen professional driver, dad had "Gentleman of the Road" taped to the back of his taxi-van. You couldn't find a more patient driver (unless he was driving us to a bus and we're running late or if the liquor store was closing.)

No matter how carefully you drive, human brains just can not pick out a dark thing that's practically stationary against another dark thing when you're in a vehicle moving >50kmh.

And our kids walk to the school by themselves if it's less than 3km iirc, and lots of those roads don't have sidewalks. Lots do, most probably, but in rural areas not every road has a sidewalk. And it's dark most of the year.

So you really get taught to wear at least a small reflector. It's not because of inconsiderate car-brained drivers. It's because humans don't have HD thermal vision that keeps perfectly up at high speeds.

This video might illustrate it better. (Pun intended.)

https://youtu.be/38xkAV8YC4k

Someone with a reflector can be spotted roughly 150m away, whereas some one without one from about 40 meters. Going 60km/h you travel 40m in 2.5 seconds. The average reaction time for general road users is put around 1.5s. Leaving you a whopping one second (1s) to slam your breaks, and even then you won't make a meaningful difference. Whereas the driver seeing someone with a reflector has almost 10 seconds, leaving them with 8.5 to reduce speed and dodge the pedestrian a bit.

So while I don't own a car, but an ebike, and take public transport and am against car-brained culture, in this instance it's you demanding everyone in countries with long winters spend all of their driving time driving about as fast as one can run, in order to have enough reaction time to avoid pedestrians without reflectors. And I think you understand that while we all dream of better public transport and less car-brain, in this instance wearing a tiny reflector you literally get for free from most places (my bus pass holder is one, for instance, because hauling hailing down buses is a lot more effective with a reflector than a dark mitten) can't be such a bother. Also you can just take it off when you get to where your going and pocket it if it so bothers you.

Also, what about pets?

Most pets nowadays here have either reflective "clothing" or leashes/bands with small leds. And a lot of the time you just spot a dog in a reflective harness and perhaps a leash hanging in midair until you see the person.