I think the responder means that duplicate code is usually easy to refactor into single methods. Typically I see copy pasted code that is changed just a little bit. However much of a duplicated function can be broken into smaller functions and the redundant code removed in favor of calling into the functions. Often what is left then becomes easier to reason about and refactor accordingly. I love the PRs that I make which delete more code than I add but still manage to add functionality. It doesn’t happen often but it’s fun when it does.

If your primary exposure to programming is only typescript or JavaScript maybe you shouldn’t be jumping straight into something like rust. JS is a high level language and rust is aimed at the lower levels where things can’t be as automatic. There are many languages out there like C#, Kotlin and Swift that will help you get used to the idea of strong types and immutability.

I wish I could say that Google is better at that. It’s basically the same story but with even less humans to talk to when you’re flagged for doing something wrong or in the case of Google your former college roommate whom you haven’t seen in 10 years did something wrong. It’s the price all mobile devs pay unless they only want to distribute to a small subset of users who have liberated their phones.