I would call that using a subset of OOP features[1], not avoiding it entirely.
But I guess there's no point in arguing over semantics.
[1] As Wikipedia defines OOP: "a programming paradigm based on the concept of "objects", which can contain data, in the form of fields (often known as attributes or properties), and code, in the form of procedures (often known as methods)." https://en.wikipedia.org/wiki/Object-oriented_programming
It's not classic OOP without inheritance and virtual functions.
But nobody seriously uses virtual functions anymore, except where they would need to use function pointers, and for precisely those uses virtual functions are way better: cleaner, safer, often faster.
But I guess there's no point in arguing over semantics.
[1] As Wikipedia defines OOP: "a programming paradigm based on the concept of "objects", which can contain data, in the form of fields (often known as attributes or properties), and code, in the form of procedures (often known as methods)." https://en.wikipedia.org/wiki/Object-oriented_programming