A framework is not a collection of libraries. You are still writing the top level code that glues all the libraries together.
A framework is that top level code, and it provides extension points or a pluggable system for the parts the framework author anticipated you needing to customize.
Works great within the boundaries, but gets very difficult once you want to step outside the framework author's preconceived notions about what one would want to do with their framework.
With the library approach, you have to invent some of your own conventions for routing and such at the top level, but you have a full understanding of it and can more easily extend it to handle new use cases.
Most projects outgrow a framework, at which point they tend to invent their own but it's a huge amount of technical debt to handle.
