Researchers have found that almost all road users break the law, but the reasons for the infractions differ between modes, with cyclists doing it to save their necks.
Regarding riding on the sidewalk/crosswalk, I was only speaking of safety for the cyclists themselves. Especially the sidewalk may seem safer, until a car coming out of or turning into a driveway runs into you because they don’t expect someone moving at bicycle speed on the sidewalk.
Regarding riding the wrong way, I was only speaking in the context of when there is car traffic on the same street. Of course, if there are no cars then there’s no added risk to riding in any direction.
~~All ~~ Many of these “worsen safety” are irrelevant generalizations at best.
(edit: Ok, the last three bullet points about headphones/helmet/lights are more legit.)
Regarding riding on the sidewalk/crosswalk, I was only speaking of safety for the cyclists themselves. Especially the sidewalk may seem safer, until a car coming out of or turning into a driveway runs into you because they don’t expect someone moving at bicycle speed on the sidewalk.
Regarding riding the wrong way, I was only speaking in the context of when there is car traffic on the same street. Of course, if there are no cars then there’s no added risk to riding in any direction.