The safest infrastructure are ones that split pedestrian / bicyclist / motor traffic as much as possible, for obvious reasons. But that infrastructure has fallen out of favor as of late. "Complete streets" are the new fashion trend, and are significantly more dangerous, by combining these forms of traffic altogether and just sort of hoping it all works out. But, "complete" streets are super cheap, and give the illusi…
In my opinion isolating separate transportation modes is only good if it is complete isolation but that's never feasible in a city. Too expensive and space-inefficient to make every intersection collision-free for cars, bikes and pedestrians. If you separate cars, bikes and pedestrians most of the time but their paths cross at intersections then you have a problem because drivers might not expect a sudden bike lane o…
If you design your intersections correctly, cyclists do not appear out of nowhere, they always intersect at right angles with the car lane (https://bicycledutch.wordpress.com/2014/02/23/junction-desig...). That hugely increases visibility of cyclists for car drivers and vice versa, and makes eye contact possible.