Predictability and not jumping in front of cars is unrelated to not being in a crosswalk. Crosswalks actually worsen these aspects, as they make drivers more prone to needlessly slamming on their brakes to wave people out while also fostering a sense of pedestrian entitlement instead of respectful temporal negotiation.

It's really not hard to look at traffic (all types), spot the existing gaps, and navigate within them. On some roads this is impractical due to traffic levels, but in most areas these type of roads are the exception.

(I suppose it's not surprising to be downvoted for saying this, as California has some of the worst drivers I've seen. It's rare that I am able to start walking and successfully pass behind a moving car, without having the driver needlessly stop while looking annoyed and acting like they're doing me a favor - even in parking lots! But frankly, anyone thinking of themselves as a hacker should surely understand and respect the value of down-to-earth informal negotiation and the peril of overformalized systems).

Perhaps it could be due to the fact that you are legally required to yield to pedestrians in a crosswalk? Not to say that people do yield often, but once a pedestrian is in a crosswalk, not yielding is a great way to get a quick ticket.

Yes of course that's what it's due to. But those laws are made for people who need/want traffic to stop so they can take their time, which is understandable. But when you're willing to wait three seconds on the curb for the one last car before a large gap, but you have to turn your entire body away and pretend to daydream just so that it won't needlessly stop, sensibilities have gone too far in the other direction.