I have no idea as to the long-term viability but your comparison with ownership is missing the point. The idea is that you just find one where you are, leave it wherever you go. Owning one is a much bigger hassle because you have to worry about theft, and maintenance, and storage.

Your barrier to entry point is fine, but the reason a person doesn’t buy one is that you take it somewhere and then have to deal with a scooter. Either you need to lock it up, or take it in places with you, and you risk having your scooter stolen.