inheritance to avoid code duplication

What no, inheritance is not for code sharing

Sound bite aside, inheritance is a higher level concept. That it “shares code” is one of several effects.

The simple, plain, decoupled way to share code is the humble function call, i.e. static method in certain langs.

If you used good objects, you’ll only have to make the change in one place

IMO that’s generally a retroactive statement because in practice have to be lucky for that to be true. An abstraction along one dimension – even a good one, will limit flexibility in some other dimension.

Occasionally, everything comes into alignment and an opportunity appears to reliably-ish predict the correct abstraction the future will need.

Most every other time, you’re better off avoiding the possibility of the really costly bad abstraction by resisting the urge to abstract preemptively.