There's a now well-known guideline that says "prefer composition over inheritance." When I saw that, it clarified a lot of things. While much of software design can theoretically be approached in terms of class hierarchies, that's rarely the right place to begin, since after you start preferring composition, inheritance is mostly just a tool to achieve polymorphism.

It's a bit of a tangent, but I think the "class Dog extends Animal" type of tutorial did a lot of damage to impressionable programmers. Because it's completely abstract and basically meaningless, it's impossible to look at it critically and discuss why you would choose this or another approach, so the idea of class hierarchies just becomes a sort of dogma (so to speak).

Inheritance is great, just depends how you use it.

I've never once reached for it for building servers.

For games? All the time.

Inheritance is often used as an enabler for polymorphism in languages that don't support it in any other way.

Somehow, it leaked out and convinced everyone that it is a good thing on its own.

So it is good that most Rusts introductions tell you that you should favor composition over inheritance in multiple places:

https://rust-for-c-programmers.com/ch20/20_3_rust_s_approach...

If Rust pushes any concept it is the use of traits: https://rust-lang.github.io/book/ch10-02-traits.html