Edit: I very much hope I'm wrong. I do see a danger of a future where a small percentage of people work long hours and everyone else is unemployed.
Only very poorly run ones with crappy per-hour productivity.
Still means a longer job search, but it's definitely possible.
Key trick: ask for shorter workweek only _after_ you have the job offer. That way they don't just filter you out in advance, and they're already in a mental state of wanting you.
I've negotiated for shorter workweek at three jobs so far, and did it this way at last two. And people who have read my book on negotiating a 3-day weekend (https://codewithoutrules.com/3dayweekend/) or that I've interviewed about their independent experience doing this (https://codewithoutrules.com/2018/01/08/part-time-programmer...) have done it as well.
But the reality is that being constantly tired is unproductive and having 50% more time off is huge.
Or do as I'm striving to do and work 5 days a week for less and less of the year. I aim for 35 weeks, basically 2/3 on, 1/3 off. And then I find when I consult for 2 or 4 more weeks it's like a bonus.
It also allows you to work a little harder on Fridays when there's a tanigble endpoint.