1. We may be at the peak complexity that our population will support. As the population stops growing, and then starts declining, we may not have the number of people to maintain this level of specialization.
2. We may be at the peak complexity that our sources of energy will support. (Though the transition to renewables may help with that.)
3. We may be at the peak complexity that humans can stand without too many of them becoming dehumanized by their work. I could see evidence for this one already appearing in society, though I'm not certain that this is the cause.
1. Human potential may be orders of magnitude greater than what people are capable of today. Population projections may be wrong.
2. Kardachev? You think we are at peak energy production? Fusion? Do you see energy usage slowing down, or speeding up, or staying constant?
3. Is the evidence you're seeing appear in society just evidence you're seeing appear in media? If media is an industry that competes for attention, and the best way to get and keep attention is not telling truth but novel threats + viewpoint validation, could it be that the evidence isn't actually evidence but misinformation? What exactly makes people feel dehumanized? Do you think people felt more or less dehumanized during the great depression and WW2? Do you think the world is more or less complex now than then?
From the points you're making you seem young (maybe early-mid 20s) and I wonder if you feel this way because you're early in your career and haven't experienced what makes work meaningful. In my early career I worked jobs like front-line retail and maintenance. Those jobs were not complex, and they felt dehumanizing. I was not appreciated. The more complex my work has become, the more creative I get to be, the more I'm appreciated for doing it, and the more human I feel. I can't speak for "society" but this has been a strong trend for me. Maybe it's because I work directly for customers and I know the work I do has an impact. Maybe people who are caught up in huge complex companies tossed around doing valueless meaningless work feel dehumanized. That makes sense to me, but I don't think the problem is complexity, I think the problem is getting paid to be performative instead of creating real value for other people. Integrity misalignment. Being paid to act in ways that aren't in alignment with personal values is dehumanizing (literally dissolves our humanity).