> huge nuisance on the bike paths because they're faster than everybody else
I doubt this, there is a huge range of people traveling at different speeds, from road bike users, to ebike users, to kids and parents. Why pretend everyone is doing the same speed?
I think you are seriously underestimating how fast recumbent bikes go. They can reach 40-50 km/h without too much effort, compared to the average cyclist going about 20 km/h.
In Europe e-bikes are separated into two categories. My country has a "regular" e-bike which provides assistance up to 25 km/h, and is treated like any other bike. A "speed pedelec", on the other hand, goes up to 45 km/h and is treated like a moped. It often isn't allowed on bike paths due to the danger the speed difference poses, and it is even required to have a license plate!
So no, just because they are all bicycles doesn't mean they can safely be mixed - just like having a tractor going 40 km/h on a motorway where the rest of the traffic goes 120 km/h is not a great idea.
Easy: you make it physically uncomfortable or even impossible to drive any faster than 50 km/h.
Simply putting up a speed sign doesn't work, we have known that for decades - you need to actually design the road for the speed you want people to drive. You're not going to drive 200 km/h down a narrow alleyway, for example, you're going to drive through there at walking pace.
I used to ride a regular trek (not even a road) bike at excess of 45km/h uphill, overtaking some slower cars. I see no point in this dual-style speed separations for e-bikes, any athletic person can do the same damage on a regular bike.
> I used to ride a regular trek (not even a road) bike at excess of 45km/h uphill, overtaking some slower cars.
That's fast for sustained uphill. I wouldn't have been able to match that in my best days. Consider going pro, that's not just 'any athletic person' that's insane. TDF riders average at about 20 kph (12-14 mph or so) uphill...
I doubt this, there is a huge range of people traveling at different speeds, from road bike users, to ebike users, to kids and parents. Why pretend everyone is doing the same speed?