But once-an-hour does not a transit system make. There's a false dichotomy here - the choices aren't car vs. shitty transit. We can very well have good transit (i.e., arterial mass transit with frequency of every 10 minutes or better).

The problem with infrequent transit, particularly arterial routes, is that it completely wipes out the possibility of transfers. When your frequency is once an hour (with a high variance for on-time performance), people cannot rely on the transit method for making connections. Moreso, decreasing frequency increases total trip time for most people by a factor larger than the actual frequency drop (which is to say, a decrease in frequency of an arterial route results in a very large increase for most whole-trip times). A highly frequent (i.e. every 10 minutes or better) trunk line is the bed rock of any mass transit solution, and is absolutely non-optional.