This is a great quote that captures the real challenges of the last mile. Notice these challenges are not technical. To adapt a quote from Tip O'Neal (Speaker of the U.S. House (D-MA) circa 1980s) .... All local loops are local.
"The last mile. It sounds easy, it's only a mile, after all – but the problem is, there are just so darned many of them. Wireless or Fixed, the last mile is a massive, poorly-scaling problem that manifests itself with trucks, cherry pickers, tower climbers, backhoes, manholes, labor unions, vandals, and byzantine local regulations and by-laws. What's to love? But as wireless modulation schemes approach the Shannon-Hartley limit, the last mile will increasingly be where we see networks scale to meet the surging demand for mobile capacity. "
From a meeting notice of the Telecom Council of Silicon Valley.