I live in Switzerland where 45km/h speedbikes are fairly popular (since for once our laws are more lax than in most European countries).

I don't really see how they're more dangerous than scooters in the same vehicle category.

The big difference is that many people drive e-bikes on bike paths or even pedestrian paths, while scooters tend to stick to roads.

No one with half a brain / common sense rides their ebikes at such speeds on pedestrian paths.

How would you prevent people who don't even have that from buying these bikes?

Don't prevent them from buying them, prevent people from riding that fast on sidewalks.

Another difference between e-bikes and scooters is that e-bikes do not require a license to drive while scooters do. One of the reasons for the speed limit on e bikes is to avoid this license requirement.

45 km/h e-bikes come with all the requirements that apply to 45 km/h limited scooters: license, plate, insurance, helmet.

The bicycle helmet instead of the Mofa/Töffli helmet is not in the same league. Cool they are (still) allowed, just like the Elektrotöffli[0].

And our laws are often more lax then Europe's. Specifically when it comes to freedoms (like weapons & privacy). Source: former EU citizen.

[0] https://emovemotors.ch/

It would be good if they went 30-35, so that you don't impede traffic on streets with a 30km/h limit. I don't think the additional 15% speed would make that much of a safety difference, compared to cars overtaking you.

It'd be dangerous to pedestrians and non-motorised cyclists though.

Of course, fit cyclists can cruise at 30+. But to get to that level, you've to put in serious effort and by the time you got the power, you know your responsibilities too. But giving anybody 30km/h vehicle that is legal on shared paths ain't good idea.

If you're afraid of cars overtaking you, get a small motorcycle.

I wonder if sth. like an electric Vespa would be feasible. You would be able to pack in more battery than an e-bike, but the last mile would be a problem because you can't just pedal the rest of the way.

Not only it's feasible, it's done. Cf. Gogoro for the most iconic ones (but there are plenty of other brands too).

The problem in Singapore is you need to get a COE for motorbikes. They cost at least 5x what am ebike would cost. I want an electrical assist bicycle that goes 50kmh and is nimble not a scooter that goes 80kmh, costs an order of magnitude more and rides like a death trap. I'd be happy if they provided some sort of intermediate license with a test for faster ebikes.

Check out unumotors.com

I average between 30-40kmh riding without a motor. Ebikes should be limited to 50kmh