That's why I said "a lot of the time". Not always. And it's not really a problem to de-DRY things, literally just copy/paste and make the change you want. The bigger problem in my eyes is when the requirements start to diverge people just add an if branch and soon you have a function/component that does 7 different things depending on how it's used and it's a big buggy mess.

It's also possible in many of these cases to identify sub-patterns you could abstract, to create a set of tools you can compose in different ways in order to satisfy the different use cases. Instead of one function/component you make multiple, and use them together.

All this stuff is just basic programming but I've mostly given up trying to preach about it. Most people don't care, and even if they did care they just don't have the talent to write really good code. It's rare to find a dev who does really solid work. In my experience you either do it because that's who you are, or nothing I say will make any difference.