make a simple web application with just image uploading and user management
I would skip addition of any unnecessary framework to the implementation, just for the sake of having it. However, if there are good functional and security gains from using one, then i would double check that framework to make sure that it suits my project needs.
Basically, i would skip adding dependency of web-framework to my project if there are no gains/benefits from it. Adding layer of abstraction (some third-party framework) to the project potentially increases complexity and dependency matrix of your project. Thus keep it simple stupid and don't over engineer it.
However, there are some type of functionality which is supported out of the box in natural in the web-framework of your primary programming language. Take C# as an example, ASP.NET MVC is a framework that
naturally support user management, data validation, model-binding, routing, etc.... What is left is just configuring the functionality, and you are done!