Seems like all anti-work propaganda (ie: r/antiwork) to me, there's no meat. You could turn this post into an inductive proof saying it is so obvious that having X-1 days is better than X days of work until you get smacked in the face trying to hand wave that 1->0 will have no impact on productivity.
This ignores that there have been trials about this. Companies trying 4 day work weeks have found their workers to be more productive.
Also, consider that worker productivity has gone up since the 70s, but wages haven't kept pace.
In surveys, most people say they'd rather have 4 day work week. 5 days is in second place. then it goes down from 3.
https://www.npr.org/2019/11/04/776163853/microsoft-japan-say...
I'd compare it to getting rid of smaller coins. Sure, it would cause some rounding hassle, but the last time we got rid of a coin the smallest remaining one was worth more than a 2020 quarter.
It seems pretty obvious to me, based on the non-linear utility of money, that as productivity increases the ideal work week shrinks. Is that not a good enough sketch of a proof?