David Rolfe Graeber (/ˈɡreɪbər/; February 12, 1961 – September 2, 2020) was an American anthropologist and anarchist activist. His influential work in economic anthropology, particularly his books Debt: The First 5,000 Years (2011), Bullshit Jobs (2018), and The Dawn of Everything (2021), and his leading role in the Occupy movement, earned him recognition as one of the foremost anthropologists and left-wing thinkers of his time.
The thing is there is no tipping point. You have small size hunter gatherer groups who are egalitarian and others aren't. Same for agricultural societies and cities and on and on. There are even groups that change depending on the season. The Dawn of Everything is a very enlightening book about this topic