I've spent multiple-year periods using each of Java EE, Spring, and no formal framework (in practice, Guice for DI, Tomcat/Servlets for web, lots of libraries, and lots and lots of homebrew stuff). I can say with confidence that if your goal is just to build a sophisticated application, there's no advantage to using the frameworks.

They include a lot of functionality, but beyond demo-scale applications, you will spend as much time fighting the framework as you save by using it.

The frameworks probably do save you time in getting started; Spring Boot certainly has a pretty smooth experience going from nothing to a running project with a controller, database, etc. But that's a tiny expense in the lifetime of a project.

EE might give you some kind of confidence that you can port your app between app servers (or different releases of an app server!). If you work in an environment where some idiot up the hierarchy has decided everyone should use app servers, that might be useful, but there's no point setting out to create such an environment.