I've been doing Python professionally for a while (~10-ish years in backend web dev and file processing), and while I don't like how exactly the author described dunder methods as "legacy", it's still not a language facility I reach out to often because, well, it's sort of odd coming from a C# background. The author has blog posts about Java, which isn't that different from C#, so maybe that's the reason.

Maybe as I grow to think of the "big picture" architecture-wise with my code, I will start incorporating dunders, but until then...