My guess is he’s referring to the way that types are fundamentally optional no-op statements in python, and therefore the level of “typing” in a given project is necessarily opinion-driven and can only be enforced through building up a lot of tooling, like making sure a type checker passes or fails all code going into deployment or CI. And even in the best case, types are duct-taped on, so there is no such thing as “perfectly type-safe”
So as soon as you have two developers on one project, you have two different opinions about it.
So as soon as you have two developers on one project, you have two different opinions about it.