I disagree with (5), that the long-term historical pattern is acceleration (and more specifically, I don’t think that the first three charts in your linked piece are sufficient to demonstrate this).
At the frontier, real GDP per person growth has remained remarkably constant for the past ~200 years.
The growth rate for the world might show acceleration, but I understand this as a compositional effect, as more countries leave the zero/low growth regime and experience rapid catch-up growth. But in the long-run each country’s growth rate will converge with the roughly constant rate at the frontier. Eventually we’ll run out of countries joining the modern growth regime, and I’d then expect world real GDP per capita growth to slow. This paper from Robert Lucas describes the dynamics I’m talking about—see Figure 3 in particular (world growth accelerates and then slows and converges to the rate at the frontier).
And due to the near universal pattern of the Demographic Transition, I’d also expect population growth to trend towards zero in the long-run. So I wouldn’t expect acceleration in the growth rate of total GDP either.
(FYI, I’m repeating my reasons for being unconvinced of David Roodman’s piece on accelerating growth, which are in also in this Twitter thread).
Hope this is helpful!
Should modernisation theory receive more attention in critiques and apologetics of economic development?