I think you are not going far enough though: All code is legacy code. So vibe coding's ability to make writing more code faster isn't special because it's code nobody understands: Your hand-rolled code is also bad.
Once you embrace the fact that all the code is legacy, then it's clear how writing more code, faster cannot be helpful from a maintenance POV: You are just creating more work for yourself.
And no, libraries don't really solve the problem, but might make it a bit less so if they are well maintained, because hopefully then they are someone else's problem. Eventually it can be mostly trusted and be almost not legacy. But a library that changes too often, or has a bad interface, is just legacy code which you also cannot change easily for a double whammy.
The more one writes code, the more one eventually realizes that the one way out of the problem is doing less: Not necessarily you, but just needing fewer things, in general. Because all complexity is ultimately a puzzle for someone that doesn't remember, and that's probably you a week later, or even in the way you typed it, as what you thought were the requirements might not really have been the requirements. And even if they were what a supposed expert told you they should be, that doesn't mean that whoever told you was right, and that's true even when you are the supposed expert.
Once you embrace the fact that all the code is legacy, then it's clear how writing more code, faster cannot be helpful from a maintenance POV: You are just creating more work for yourself.
And no, libraries don't really solve the problem, but might make it a bit less so if they are well maintained, because hopefully then they are someone else's problem. Eventually it can be mostly trusted and be almost not legacy. But a library that changes too often, or has a bad interface, is just legacy code which you also cannot change easily for a double whammy.
The more one writes code, the more one eventually realizes that the one way out of the problem is doing less: Not necessarily you, but just needing fewer things, in general. Because all complexity is ultimately a puzzle for someone that doesn't remember, and that's probably you a week later, or even in the way you typed it, as what you thought were the requirements might not really have been the requirements. And even if they were what a supposed expert told you they should be, that doesn't mean that whoever told you was right, and that's true even when you are the supposed expert.