Unfortunately not. While Google weeds out most of the outright spam, there are several irritating blasts a day from some asshole who thinks Schemers are interested in his notion, very strongly expressed (at first in Italian and later in English) that various Italian politicians are corrupt child molesters.
I've been marking every one of those messages with the Abuse flag for over a year now, but Google doesn't seem to have gotten the picture. I suspect that Google Groups, including comp.lang.scheme, continues to get few resources from the company, and so the machine learning being applied there is mediocre.