I know numerous people at multiple companies in the UK who negotiated working a 4 day week as a dev in return for a 20% pay cut. Not sure how common that is in

I know numerous people at multiple companies in the UK who negotiated working a 4 day week as a dev in return for a 20% pay cut. Not sure how common that is in the US, or whether less than four days a week is something employers would ever consider.