(Author here) Across several city blocks, in fact, and longer than the max range of Ethernet on normal (Cat 5/5e/6) cables.

Past ~300ft/100m, you need a repeater even for Ethernet. We would have needed at least one repeater somewhere along the line, which adds even more cost and complexity on top of needing to get permits from the city and approvals from all the neighbors in between. Anyone that says "just go get a permit from the city" has never tried doing it.