Illogical. People who can't afford 2 bed rentals don't move to the nearby street if rents are unaffordable. They move to another town where they can afford the rents. Correlation isn't causation

30 days is not a lot of time to find a place, especially if you're having to compete in bidding wars against other people. It can be especially difficult to come up with a security deposit and first month's rent. If most people have less than 1300 in savings then they can only afford a new place that rents for 600/month. I can't think of any municipalities in the area where rents are that cheap without downsizing your family into a studio. To say nothing of the burden of packing all your things, cleaning the apartment, getting enough friends to help you move out, etc.. It's not a trivial thing to do on short notice while you're holding down a job.

You know that moving costs quite a bit of money, right? If you lose your job or have a serious medical issue without insurance, you won't be able to move to a nearby town with cheaper rents.

What do you think the underlying cause of homelessness in Seattle is?

Not if they get pushed from barely being able to afford it to not being able to afford it in the span of a month or two.