Ebikes and smaller scooters seem to have standarized at 16mph (25kph). That is perfectly compatible with bike lanes. A bike in a hurry can easily go over that.
Imperfectly compatible. Sure bikes can go that fast, but rarely do. The disparity in average speed results in frequent passing which is most of the problem. Head-on collisions and clipping become a thing. That's kind of the whole ball game, and why they don't get along on paths.
Almost no bikes actually go that fast, while the scooters practically always do, which is they they drive in the middle of the lanes or into oncoming traffic. Thus head on collisions etc.
It depends on your local bike culture I guess. In the US scooters go 15mph and bikes go like 12mph if you are in street clothes, ~20mph if you are in spandex.