They have many views, the trouble is the proliferation of these views as you go through the code. You browse to a class and method, then you want to see the senders, and so you open that, and then see the implementors of a method a sender calls, and so on.
https://blog.lorenzano.eu/content/images/2026/01/Pasted-imag...
Then it sounds less like a specific problem with the 4-pane browser, or SMalltalk IDEs, or Smalltalk, and instead simply an overcomplicated way to state the obvious: large codebases are complex and difficult to navigate. No shit.
Smalltalk makes it a little harder than some languages because a method has no real idea who will be receiving the messages it sends. People have done work on implementing types (Strongtalk) to, among other things, limit the search space. But you're right that a lot of moving parts means that eventually you have to have a lot of open context to view it statically.
Another way is to trace things in the debugger, and then you get the dynamic picture.