I don't see how NYC gets to 1% let alone 6% without pulling out car lanes and converting them into two lane bike lanes which are immutable: no parking, no blocking. Now, they get blocked the instant someone opens a car door or double parks. With higher biking density comes different speed cycling so single lane biking doesn't scale.

Denver has this crazy idea also that catering to bikes is easy and cheap, the mentality is that it's mainly just a matter of paint and "share the road" signage. Meanwhile there's no driver or cyclist education program on exactly how to share the road, so it's still adversarial "hey asshole YOU aren't sharing the road!"