I think the similarity is more like a mathematical/structural one, and doesn’t hold much water in a pragmatic sense. The possible error conditions for a network call are just insanely bigger than of a function call.

Also, Smalltalk and alia of the “real OOP” kind has some extremes with regards to messaging, like the number 3 being told to increase itself by one, which would not be done this way in today’s OOP languages and not just for performance reasons.

Method calls are more of a degenerate case of a distributed system, which is significantly easier to reason about.