Exactly the point they were making. All these problems were already around at the time. In fact people didn't even see them as problems. Read gang of four, and they don't really mention working around the limitations of the language. It is as if they are not really aware how many of their problems are arising due to the language's design, and think their patterns are just a generically good to do it. People don't use a majority of them now because there is just no need for them anymore in modern languages.
Curiously, Smalltalk also lacks the idea of a function. Everything is an object; instead of a function, you have a code block which is an object.
But, unlike Java, Smalltalk is (utterly) dynamic, and you don't have to declare a class for your code block. In Java, you had to dance that dance, until lambdas were introduced to let the compiler do that for you.
"Every object in Smalltalk, even a lowly integer, has a set of messages, a protocol, that defines the explicit communication to which that object can respond. Internally, objects may have local storage and access to other shared information which comprise the implicit context of all communication."
perform: aSymbol with: anObject
Answer the result of sending a binary message
to the receiver with selector aSymbol and argument
anObject. Report an error if the number of arguments
expected by the selector is not one.