Road design, safety and Vision Zero

[Bytor]

A street redesign costs 5-10 million (at the low end)

No. Brand new residential streets are about $1M/lane-km to build and better designed streets do not cost more because it's still all the same things just laid out differently. So tha $5-10M is 2.5 yo 5km of residential streets.

ASE equipment costs thousands, and signs for it cost hundreds.

Try tens of thousands for the camera and controller in the box, plus tens of thousands more to hook it into a municipal-area network so it can report back to the central servers. A lot of the stop lights you see around are old and are running at dial-up speeds or lower. Certainly not the megabit speeds needed for a camera to send back pictures at a busy intersection.

How many cameras do you think you need to cover a residential street to get the same effect as a proper re-design? This article places each camera at $50k per year to lease and operate or the City of Toronto.

Also...roads absolutely have a maintenance cost. In fact, a top regional objection to better bike infra is maintenance and repair costs...

Not $50k/year per lane-kilometre, though.

So you're spending millions on a handful of cameras plus network connectivity that likely won't last the decade before neding replacement, or you can spend millions on a road that will last 30+ years, both to the same effect.