No!

- Parametric polymorpism isn't OOP, pretty much every halfway-decent language has it (including Haskell, which is as functional as they come).

- Boxing in Rust isn't what you think it is - it's just heap allocation (more like malloc than the monstrosity that is boxing in Java).

- Again, operator overloading isn't OOP either. Seriously, is it that hard to believe that "you get to use + and - with your own types" is an expectation independent of any paradigm?

> I must have gotten the wrong idea.

Yes. Go and Rust are both very far from what most people would consider "OOP".