A policy of wheels in roadways only and pedestrian primacy will keep cities alive. Force cars, bikes, skateboards and scooters to contend for space (dedicated non-motorized lanes helps) but preserve the pavement for foot traffic.
A bike going 10mph is going to be able to stop faster, maneuver quicker, and do a lot less damage to a pedestrian if they hit them than a car going 55mph would to a biker going 10mph.
Do you really just want to see more bikers and skaters killed? Because that's the primary outcome of "wheels belong on the road". What you're arguing for is unprotected human beings getting ground into the pavement by a machine that may not even feel the impact.
The fact that most of the US forces bikes to behave like cars is one of the worst urban policies we've ever come up with, and is responsible for untold numbers of deaths and serious injuries. A bicycle is not a car and should not share road space with cars unless pedestrians would also be forced to share road space with a car. Compared to 3000lb machines capable of maintaining speeds over 100mph, there is absolutely no difference between a bicycle and a pedestrian. They all bounce off the windshield exactly the same.
"Get these bikes and scooters off my sidewalk" translates directly to "I don't care if these bikers or scooter riders get killed as long as it doesn't inconvenience me".
I strongly hate cyclists on sidewalks. If they dread pedalling on a road and there are no bike lanes, they (we) have the option of walking, using public transport or drive a car. And campaigning for more bike lanes: this is how they did it in the Netherlands https://www.theguardian.com/cities/2015/may/05/amsterdam-bic...