Yes, but the obvious goal was to squeeze more labor out of the population by removing the religiously supported 'rest' day.

entrenched religious authorities used the rest day as a lever for religious observation laws and such.. both sides, secular red and traditional religious groups, pushing hard to "command" the week.. that is a guess from afar

Absolutely, it's a tithe on time. It's power structures competing for influence.

Actually, there were more rest days under the new system, they just weren't synced up (different people would have a different rest day).