My point is that scooters are not new offenders (or even the worst offenders) of blocking the sidewalk, but no one complains about the cars, that's just accepted.
No one in your neighborhood perhaps. This varies considerably.
The car might be a rental too, doesn't really make a difference.
I tolerate far worse externalities from my neighbors because they're my neighbors and I want to minimize pointless conflict for their emotional benefit as well as mine. Business that create externalities in my neighborhood for the sake of corporate profit, on the other hand, can either pay me and my neighbors in cash to deal with the externalities (with a decent profit margin for our time and effort) or they can go f* themselves.