A competent lead programmer will choose a structure that adheres to common best practices and is maintained by a community. Also known as a framework.
>If you don't understand then you are either writing huge amounts of documentation and test code for your custom solution, or you are acknowledging that your app will be unmaintainable once you leave your position.
200,000 libraries, 50 of them good. My point exactly. A well written framework has already done the curation for you and has a community of people working to make those components even better for YOUR USE CASE.
>Both are signs of inexperience.
I guess I won't be hiring you then. If a candidate comes in and says "I don't trust frameworks because they are complex", I say "Thanks for your time."