You need a license to drive a moped, you can hear them coming and people never drove them up the sidewalk, it's completely different.

We didn't need a license, by virtue of the displacement of the stock engine being small (IIRC the limit was 125cc? Or maybe even less). They also had to have pedals, so small motorcycles or vespa-style scooters did require a license. Or at least a registration.

The mopeds would barely go 30mph as sold. That was hackable though if you were so inclined and had a set of wrenches.

Too late to edit but I was way off on the engine size.... 50cc displacement or less.

Yeah 49cc mopeds that aren't registered appear to still be a thing where I am (Boston). And I think it's 49cc 2-stroke so equivalent to like a 90cc 4-stroke (whether that ends up violating a different emissions rules, I don't know).

Still, parking is such a racket in Seaport, including unnecessarily strict ticketing on motorcycles, that I don't blame the delivery guys for using the mopeds. I'm not sure what their realistic alternative would be.

Mopeds are still around. It’s completely different than a bike that can appear to be a normal bicycle on a bicycle path.