It seems like something that could potentially be made much cheaper with a collection of drones with 360 cameras. they could all be programmed to fill out areas relatively quickly I think. It might not be street height which would be a bit of a loss, but an open dataset (with appropriate face/license plate/etc filtering) would be worth that I think.
There's also OpenDroneMap, which is more drone-focused and captures full 3d point clouds, but that still isn't quite the same as what you're proposing.
The 360 cameras are cheap but getting things accurately localized (if you care about that) and having LiDAR like google has (also if you care about this) is a bit more expensive.
I think one promising route might be to stick a 360 camera on some random cars in exchange for a fee (similar to how ads are put on top of Ubers/Taxis). I bet you could cover a city pretty quick that way, as long as you figure out how to offload the data. Maybe an agreement with a taxi company to plug into the top of the cars a couple times a week.