I think the comparison to older empires are nonsense because their society wasn't nearly as complex as ours. They didn't have population explosion, no on-demand infrastructure, they weren't dependent on oil. The higher you go, the harder you'll crash.
I agree that we're on the early stages of collapse though.
Just look at all the major issues that came up in the last 30 years, none of that shit is normal, none of that shit came close to being solved and problems are only increasing over time.
In case you're wondering what specifically I mean: Basically anything: From political radicalization, to people getting more fatter, to environmental issues. Life appears to get more comfier, but comfiness isn't cheap. I think poorer countries will have it easier in the future, since there's not that much infrastructure established that can collapse.