It does vary. I'm not saying that in cities like Boston and New York, literally no one would ever get a ticket, but people pretty much will take whatever they can get away with for the most part. Historically, West Coast cities were considered to have at least a modicum of enforcement but I expect that's very scattered these days.

So, yeah, there's technically a crime of jaywalking but in practice it's mostly limited to whatever you feel you can get away with absent being run over.