There are some valid cases where extends really can help, and IMO the language would feel limited without it. Maybe if the language designers had their time back they could have taken an approach like Golang with nested structs and syntactic sugar for calling their attributes/methods.

The main reason I see new devs opt for extends, is because that was 99% of the content in their Java 101 programming course, not because it exists in the language. Imagine how many more `friend`s we would have in cpp if that was crammed down everyone's throats? :)