Longer than that. At least as early as the french revolution.
The elites keep the population paralyzed by fear via asymmetrical military force, and through complacency with greasy consumer slop. This is a very good system (for the ones at the top of it) for a long time, but systems are subject to entropy. The managerial elite types who keep this system running are decadent, focused mostly on ego and personal excess now, they're under a microscope so when they flout the laws they force us all to follow, it gets around, they can't even keep the consumer slop plentiful enough to keep us complacent, and with the breakdown of law&order for the common person, the fear of their monopoly on force also diminishes. You have an increasingly large segment of the population with nothing to lose, and there's very little the elites can do about it at this point that doesn't make that segment of the population even more adversarial. It's a losing battle every time it comes up in history. If you don't have some way to take those fighting-age males with nothing to lose and turn them outward, they'll eat you, and we really don't have anything to turn them outwards on that doesn't result in destruction of everything.
The elites could make a few changes, go back to traditional morality structures and some kind of neofeudalism, and then start giving goodies to that segment of the population, and stave off their own downfall for another 100 years, but they're literally so addicted to doing drugs and fucking underage escorts and the social mileu, it just won't happen. The only segment of the elites that are even attempting to make these changes are the transhumanist technocrat types like musk or even schwab, but the entrenched more "legacy" managerial elites are throwing up roadblocks to this. The truth is, there's like 50 people you could murder tomorrow and guarantee the downfall of the established order, or at least set it back for 100 years. I think those people realize it, and so they use their policy-setting power to try and reduce population to even the playing field. If you're 50 to 100 people with a lot of money and half of 8 billion people are openly trying to kill you across the entire planet, you're fucked. If there's 500 million people on earth densely packed into 15 minute cities with no resources besides what you give them, you can just bribe off some cattle to be your security, fuck off to a castle in nature, and even if all 500 mil want you dead, they can't really do all that much about it.
Don't let yourself be fooled into thinking we're at the end of history. Shit's gonna get pretty spicy in the next 100 years