Curious among folks here: Are you aware of companies that allow for or even encourage four day work weeks?
The trick is being senior enough (or in demand enough) that you can get one company to agree to a 32h week for you (and be willing to walk - I've interviewed with very interesting companies who weren't willing to consider it, and so we ended the discussions).
Once you have it in some form or another, you're good. It's just a condition of employing you, early in discussions with other companies.
Our company hired a greybeard with a rock solid condition of his employment being a four day work week. After that, it was much easier for "normal" employees to switch to it since management was familiar with the idea and saw that he was a very productive employee.
I switched to four day work weeks when I was 29 (based on his example) and have been very happy with it.
That's the secret. Being willing to GTFO if they don't meet your terms. And being good enough at what you do that they're willing to meet your terms.
My current employer, on initial contact, wasn't willing to consider fully remote and 32h/wk. Then a year later, they came back and were willing to talk because they'd been trying to find someone with my skillset locally.
For example, if a divorced guy gets his kid on Friday and Saturday every week, it turns out getting every Friday off is a super-valuable benefit for him, and now you can hire a $120k programmer for $70k.
https://www.databricks.com/blog/welcoming-bit-io-databricks-...
Only left them due to compulsory redundancy due to cost cutting.
The whole idea is to generate ~95% of value with 80% of the work time, and to split the difference money-wise.