@jefftk Practically speaking, running by default seems more difficult since in most situations where I could either run or walk, I find that I am encumbered by something like a backpack (which would bounce and be uncomfortable) or a cup of tea.
I also get the feeling that running is slightly more likely to lead to collisions, which is a bit hazardous for people around you.
@zebrask if this were the only reason this would push strongly in favor of trying to overcome the aversion
@zebrask my backpack doesn't really bounce when I run (and I'm wearing it for probably a bit more than half my running). It's mostly a matter of adjusting it to fit snuggly. If it still bounced with a good adjustment I'd buckle the waist strap.
a Schelling point for those who seek one
@jefftk Presumably the reason why it's not the default is because running is less energy efficient per unit distance¹: https://pubmed.ncbi.nlm.nih.gov/15570150/
We're no longer energy constrained (and in fact people would probably prefer to burn more calories), but our instincts and aversions are still tuned to efficiency.
¹I think this actually depends on walking speed, but you need to walk pretty briskly for walking to be less energy efficient per distance than running.