alt Hacker NewsCode always was, it's supposed to be malleable. It's why it's long been said that code is a liability, not an asset. It's the data you generate with that code that's your asset. You can always rewrite the code.
We, in general, are just very bad at letting code ossify, or for this metaphor, dry out and crumble. AI does not solve this problem and I fully expect to see situations where AI generated code becomes so hard to work with that even LLMs prefer to throw it away and start fresh again.
Code was malleable only to a developer with great code comprehension. In my experience, this was actually very rare. I think part of the reason is, you don't get any recognition for modifying a few lines of someone else's code compared to "I created this new library/app to solve this problem for our org!".