Riding a bike on the sidewalk (or a divided bike path) is actually pretty dangerous. Cars aren't expecting there to be 15-25 mph traffic when they pull in to driveways or make turns.

The most common type of bike accidents are cars failing to yield when turning or using driveways, and divided bike paths and sidewalks only make it worse.

I try to be super vigilant when crossing crosswalks and driveways when using the sidewalk, but pretty much all of the close calls I've had have been because I was riding moderately fast on the sidewalk.

But it wouldn't solve many of the complaints that bicyclists and pedestrians have.

That's done in Europe, where sidewalks are wide enough. Most sidewalks in the US aren't wide enough to include a bike lane.

It might solve the complaints motorists have, but then you'd have the complaints of pedestrians to deal with. In two major cities in my country, bike lanes have been added to the pavements as a bright red stripe on the side of the pavement closest to the road. Local pedestrians shouldn't walk on that portion of the pavement, but they still do, and if you ring your bell or shout for them to give way, they either ignore you or yell at you. It’s actually much faster to simply cycle on the road with the cars.

We should take land away from motorists, not from pedestrians.

That's how it is in Berlin. I'm surprised people think it is so weird.

Bikes are more like pedestrians than like cars.

Good god, please no! The most harrowing pedestrian segment of my commute isn't crossing the 8-lane highway with poorly timed lights (though that's a close second). It's the one block where the bike lane is officially marked as being on the sidewalk.

And raise an even larger amount of complaints from pedestrians.