That functions well as an "I was riding my bike and guess what happened" story, but as an argument against clipless, it's completely absurd.

I use clipless in stop-and-go traffic and love it, but as others have said, "should I go clipless" isn't an answerable question in the context of a commute. People make it work with platforms, with clipless, with clips, with those Powergrip things which look silly as hell to me but what do I know. The reasons behind their choices have very little to do with objective advantages and disadvantages, and everything to do with personal taste. The biggest problem is that it's not easy to try all three and see what you like best. If you have a friend with clipless pedals on a bike that more or less fits you, and the same shoe size as you, you could maybe try them out, but otherwise you pretty much have to buy the package (which doesn't have to be that costly btw).