Have been there, have also been to the Netherlands. There isn't really a big difference in the total space available, in my limited experience. You can find a big difference for a photo op, sure.

Based on where I have been, I guess the big difference is that the Dutch allocate continuous space to bikes and the British have a patchwork of bike space and parked cars.

The Dutch use of space seems more effective, the space they use for bikes is connected, rather than unconnected/ineffective bits.

But note that on the first photo, you see four streets meeting at an intersection, that's eight sides, and there are cars parked on only two of the eight. Look at the the next intersection you pass on the way somewhere and compare the number of sides with parking space with that "two".