[maxsilver]

> Can you provide a source for this? (especially concerning the separation of bicyclists and motor traffic)

https://rspcb.safety.fhwa.dot.gov/Dashboard/Default.aspx

USDOT routinely finds freeways to be the safest roadway for all involved each year (lowest number of ped/bike/car fatalities), since it separates traffic modes.

Pedestrians and bicyclists go over/under/beside it on dedicated infrastructure, they are never on it. And similarly, cars are never on the dedicated ped/bike infrastructure, so collisions are effectively impossible from either side, due to physics.