Lol, the lead can’t spec the style, he just reviews the code and asks for changes. Sometimes it’s just that we already have a method that does a similar thing, so we should use it. Of course an AI wouldn’t know about that unless you gave it access to your code. And given how speed first AI companies are, I would never trust that data with them. But other times it’s just the leads personal preference.
I do know the feel. I was young once (seems a long long time ago). Reinventing the wheel was fun and challenging. I loved creating libraries. I didn’t actually know at the time that there were already existing libraries I could just use, this was the 90s. But it is hard to keep track of what library code exists in a project if you didn’t write it. Maybe assign them to review the library code and document it or something. Then they will know what it is at least.