Western society doesn’t increase idleness options. It actively discourages idleness by giving you ever simpler ways to use up every cycle.
Idleness leads to thinking, which tends to lead to people testing their cages.
I think it has more to do with the fact that you'd otherwise starve to death. There was no wholefoods to trade food stamps in. Also preindustrial probably any man hour had to be useful.
While today it costs next to nothing for us to feed the homeless, then it would have been almost as expensive as hiring them.
Although if food grows easily, you might expect the number of humans around to grow to catch up with it... and this mostly didn't happen (in the pre-industrial world) not because there wasn't enough time (exponentials are fast!) but because it ran into other limits, like disease.