I dont see many people who use a smalltalk that is not a smalltalk , the same way a human is not an arm, wanting to come to pharo and locked in an IDE and Enviroment. But then there are a tiny amount of them out there anyway, judging from their mailing list that is barely alive.
Gnu Smalltalk is like keeping the cherry and throwing away the cake. I think its far more important to attrack the right kind of people who believe or seek the smalltalk ideal.