Certainly true, but that's not a reason to give up on creating those abstractions, like the post I was replying to was suggesting. It's a reason to be judicious

Certainly true, but that's not a reason to give up on creating those abstractions, like the post I was replying to was suggesting. It's a reason to be judicious about when it's appropriate to create these abstractions, and in particular about when they should be shared. An abstraction that's used in just one or two places is still really easy to change. A bad abstraction used in a dozen places is a pain the ass to clean up. It's not an easy problem, and it ultimately takes some combination of experience and careful mentoring to learn to identify good and bad abstractions before they're built.