A scooter has about the same functionality as an e-bike but can go on sidewalks without seeming nearly as threatening. Use in bike lanes, go 4 times as fast as walking, no sweating like a bicycle, and more portable and much cheaper than an e-bike. If my commute is a mile from a train station on both ends, that is 40 minutes of walking a day. Probably good for your health, but cutting that down to 10 minutes by using a scooter could make trains much more useful for many people. Make it 2 miles on each end, then a bicycle is really needed. Bulky and not allowed on many subways. e-scooter could work just as well.

Plus they are pretty fun to ride.

  without seeming nearly as threatening

Quite the contrary.

Scooters are viewed by the riders as less dangerous than bikes. Result: they take more risks, especially risks to pedestrians.

A person on a scooter is barely bigger than just a person. They stand maybe 4 inches higher. They are like like a person running. A bit annoying and going too fast, but not that big a deal. A bike going the same speed is a much bigger object.

  They are like like a person running.

You've clearly never seen a scooter clip a person's ankle and break it. I have. The point of contact is not torso to torso, it's metal to ankle.

It's common here for scooter retrievers to stack multiple scooters crosswise on the driven scooter's floorboard when carrying back for charging or deployment, making it a 3+ foot wide wrecking platform.

A fit person can walk at the speed of 3 mph or 5 kph, anything faster would be in jogging/running category. A electric scooter can easily each a speed of 12 mph or 20 kph - 4 times faster which is quite significant.

A 10 minute walk becomes just under 3 minutes on a scooter, and the time saving adds up over longer distance: Suppose you live 3 miles from the closest bus/train stop, it would be an hour on foot which is not practical for daily commute; 15 minutes on a scooter, however, is much more manageable and be competitive with driving.

My office is 3km from nearest Metro station in a hot humid country. If I walk it would take me 20-30 mins and I'll reach office tired and sweaty. Current scenario, my company provides cab that drives me 20 km in peak traffic. Alternate, I take a folding scooter, which I can carry in Metro and reach office in 10 mins still presentable.

I can commute by foot (which takes slightly over an hour), by bike (which takes 20 mins but leaves me noticeably sweaty), or by scooter which takes 20 mins and has no downsides. In practice, if I can't scoot then I drive a car because wasting 80+ mins a day or arriving everywhere sweaty just doesn't cut it for me. Buying a scooter has revolutionised my commute.

Speed. When that last mile is actually a mile and half, a 9-mph scooter will let you travel it from the train station in 10 min, which is reasonable in terms of time; whereas a half hour walk on top of your train commute time probably isn’t. It makes not driving much more viable in some situations.

I know it’s silly, but Americans won’t walk. The average single car trip in America is 5.95 miles long, with many rides falling into the 1-2 mile range. That is already easy biking range, and lots of Americans could walk that, but they dont.

If electric scooters change that, even only for the able bodied who don’t need to carry a ton of gear, it would be huge.