I spend a lot of time programming against REST APIs in C# and Python, each with it’s own separate challenges.
Designing APIs is hard. Keeping the entire development team(s) to the design principals of your API design is even harder.
I would say that’s it only become a convention recently and I still haven’t seen any good arguments as to why loosing the distinction between callable and non-callable objects would be a good thing.
Your example does indeed look bad, but also goes against the advice given in the article so I‘m not sure where you’re going…