And it probably goes without saying that most people would not be OK with a pay cut--which might have to actually be more than 20% given the cost of benefits is fairly fixed.
On paper, it may have seemed like the right move, but it was huge demoralizing to the engineering org to be told, essentially: we will neither pay enough to be competitive, nor offer any other compensatory advantages, primarily in deference to this other department that we do pay well.
The morale question was apparently only considered in one direction.
Not how it happened when going 6 to 5 days. People made it happen. And OP is one of them.
People (trade unionists) made eight-hour workdays happen, but Henry Ford made a five-day workday happen[0]. As I stated, most labor rights came about because of blood, sweat, and tears. Just... not that particular one, oddly enough.
The fact that Ford's five-day work weeks were made up of eight-hour days, for that you can think unions and the hard work of many people! But the shift from six days to five, not so much.
P.S. OP was probably not working age in 1926, as they would need to be to have made the shift happen originally.
0. https://www.truthorfiction.com/henry-ford-invented-the-5-day...
The five-day work-week came about because Henry Ford declared it to be so in 1926, and wasn't made any sort of law until 1939.
Ultimately, the decision to move to four-day work weeks can only be made by CEOs or equivalents, and while some have, most haven't. At my previous company, the head of HR proposed it, the CTO agreed, and it went to the CEO, who said no. He didn't want the CTO org to have benefits the rest of the company didn't have, and didn't want to extend a four-day work week to all departments.
When they continue to have trouble filling open job positions because they aren't competing will in the market, perhaps he'll change his mind.
https://www.4dayweek.com