Sure, we had a problem with horses. But we also had a looming problem with cars, which is what the quote is (correctly in my opinion) forecasting, one which we

Sure, we had a problem with horses. But we also had a looming problem with cars, which is what the quote is (correctly in my opinion) forecasting, one which we are now starting to acknowledge (practically unsolvable currently). So the quote is very much on the mark. The horse manure problem was a somewhat related issue, but does not invalidate the quote. Could we have solved the horse manure problem without creating a pedestrian-hostile society? Who knows, we didn't even try.