We like our cyclists.
The floating roundabout does have the disadvantage that you need a bigger height difference to allow the cars to pass below it.
Or just normal engineers/managers working within a system that doesn't bleed money to "not quite technically corruption" at every step.
https://goo.gl/maps/dfKWDZjcjsKa5sjM9
There's quite a contrast between the elegance and simplicity of the bike route and the seeming chaos of lane markings of the underlying motor vehicle intersection.
And I'm not sure civil engineering jobs like this are more efficient en masse. They're all essentially one-off?
Also, bike roads are not as overly constructed like car roads (maybe just 1 or 2 layers of asphalt instead of more)