A 3-day work week (aka 40% less productivity if you assume a perfectly linear relationship between time working and productivity) would still mean a nice little gain for the capitalist compared to 1979 numbers.
If you've worked, you've contributed to that 44% productivity gain. Why should you need to revolt or organize to get what you've already worked for? Capitalists are taking a larger and larger share every year. Is that ethical?
I get that pragmatically many aspects in life are a power struggle, but "throwing the question back" is really a way of putting the burden of fixing an unfair system back on the victim.