If Inheritance is so bad, why does everyone use it?

But in work code I don’t see it much. If it is used it is light weight. Often used incorrectly for splitting code into different files rather than actual inheritance (giveaway is one one derived class!)

It makes no sense to use inheritance in the business layer, because a single feature request can make a lot of the carefully crafted abstractions obsolete.

Inheritance is like a lot specialised tools - it can be useful in some situations but I think those are rarer than supporters might thing. Completely refusing to use inheritance and always using inheritance both seem like extreme views that should be avoided.

I prefer to say that we naturally classify objects around us using fuzzy boundaries like "a house", "a cat", which don't exactly mean anything: they are templates we use later to actually generate an actual house, or an actual cat (on a piece of paper as a drawing for instance).

The world being separated between our internal classes and the interactive instances of them, we can code that way too: we look for what we actually need in a concept, name it and define only what we need, then instantiate several concrete actors interacting together. Each actor is complete, well defined, with contracts for interactions.

You can then start building on top of this more complex systems, talking in English and defining rationally the world of your little model.

If you start talking about functions, you're basically aliasing a memory address for a bunch of code: you'll goto that function address, with some parameters at some other address, do a bunch of things and put the result in another address for the next function to process. You're building at best a suite of pipelines, which ends up being a little bit too technical and static for my taste.

Another way to defend modelling a software with classes and object, in my view, without trying to talk about functions, is the blank page effect: imagine arriving at random at some assignment. You understand vaguely the business problem, now you need to code a solution. You have 6 months, will generate a few millions a year and will require a team of 10 people eventually to test, maintain, operate and debug: you start with defining functions generating functions with callback parameters in Python, or you launch IntelliJ and you do a Java class model ? I'd be terrified modelling complex problems with just functional pipelines, I think it's just way more obvious to talk about objects at all time if you're gonna do something that is not just processing inputs into well defined outputs.