Sigh. If I had a dollar for every "your compiler should optimize away X", I'd be retired. Should doesn't mean does.

Plus, no, often I can't afford a function invokation. Because it's yet another cache miss.

If all of those things don't matter (or you work on a large enough team that the benefits of abstraction are worth it), yes, add getters/setters everywhere. For the rest of us, we might have actual _reasons_ why we don't cargo-cult our code.