Unfortunately, for some “leaders” it won’t make any difference what the numbers say about 4 day work weeks.
I tried to get it implemented at a company that I co-founded, and despite presenting multiple studies showing that we would very likely save money and be more efficient, our CEO simply ignored them and kept repeating that a 4 day week wouldn’t be efficient. They had zero interest in what statistics and studies say; they’re the CEO and if their gut feeling says 4 days bad, then 4 days bad (and no their decision wasn’t due to them having information I didn’t have). I’ve heard similar stories from others.
Hopefully the results of this trial won’t just get ignored and forgotten.