Ann Arbor recently changed it's laws to reflect that - and I think the cyclists who are aware they shouldn't be on sidewalks, and the e-cyclists who stick only to the sidewalks know who they are.
Ann Arbor changed the law to make this legal: http://www.annarbor.com/news/bicyclists-dilemma-ride-on-the-....
And recently for E-Bikes as well: https://www.mlive.com/news/ann-arbor/2021/09/ann-arbor-movin....
And yes, I know that California law states that bicycles have to be on the road, but that doesn't reflect reality. And, in fact, at least in Redwood City, I never once (In 5 years of walking every day, and seeing dozens of cyclists every day) saw a police officer cite a cyclist for riding on the sidewalk - though, that isn't the case in Southern California, where I read an NYT article that people of color are routinely stopped/searched for doing so - in much the same way people are cited in some cities for "Jay Walking" - which is a universally accepted behavior in other cities.
But, one thing I think you and I can agree on, that cyclists on the sidewalk have to show the utmost in courtesy to pedestrians, and not go racing along at high (> 8mph or so) speeds - essentially occupy the same speed as your typical jogger might. Also, another topic we might agree on - Bicycle Lanes just make things safer for everyone, cyclist and pedestrian alike.
There are informal norms. Cyclists who cycle on sidewalks should be relatively new and should make sure to behave explicitly with all of the rules of the road (ie. don't run a red from the sidewalk as a cyclist, very dangerous. if you must, dismount and walk across or wait for the pedestrian light). Cyclists on the street are generally more experienced and do not have to explicitly follow all rules IMO.
"Idaho stops", ie. treating stop signs as yields is both enshrined in law in a few different areas and should be law in many others.
Idaho stops are perfectly acceptable in my view.
For example, Kentucky law requires bicyclists over the age of 11 to use the streets. (Prohibits sidewalk usage.)
Washington state law allows sidewalk usage, but also requires wider sidewalks than the Kentucky minimum, and includes a lot of very specific wording about pedestrian right of way on sidewalks (sidewalks are theirs first) and mandate being very careful in overtaking pedestrians and other cyclists.
"Free pass" for electric motorbikes? What is that person on about? Why have meaningless distinctions between pedaling or not, when the overriding goal should be "promote bike use over vehicle use"?
What societal good, what good to the citizen, is it to place burdens on e-bikes that are not pedal assist?
Although it can be applied with a bit much snark sometimes. :)