My complaint isn't that they're impassable for pedestrians and cyclists, it's their sheer size. They're every bit as big as a 5 x 5 lane signaled intersection despite servicing a 2 x 2. And I've yet to see anywhere in the US that has implemented them figure out that they can still put buildings next to them, so they're always occupying the middle of a goofy-wide strip of undeveloped land that functions as a "natural buffer" between the road and the inevitable wall around an adjacent sub-development or big box parking lot. My complaint is just that they're not urban infrastructure, just an improved suburban exchange still in no man's land, and as such don't really improve the land use of an area.