[0] https://en.wikipedia.org/wiki/Last_mile_(transportation)
The problem is not last mile. It idea that last 30 miles are not viable to run extended routes through as it gets too slow to follow the winding paths as plain buses.
The solution is actually pedestrian traffic and biking optimization for last few miles access, not tossing more cars at the problem. Not building areas in cities with crummy access to public transport. Making it less necessary to carry heavy loads personally relying on improved delivery systems instead. (Which should also create some jobs.)