I do think that slower transportation helps.

Cyclists tend to be more patient than drivers, based on my (biased) observations. As a transportation cyclist I don't really understand the mindset of many drivers. Their apparent need for instant transportation seems to override safety concerns, particularly the safety of others. Often drivers aren't much faster than I am, particularly given the number of stop lights on my commute. Many cyclists have pointed out the irony in how a dangerous driver who nearly runs over a cyclist often sits at the next stop light with the same cyclist stopped right behind them.

My guess is that cyclists are more patient due to both selection effects (more patient people are more likely to become cyclists) and driving actively decreasing patience.