I'm honestly not sure if you wouldn't be better off changing the name of the service to something else at this point. People who just want to download binaries won't care what the name is, and developers who want to use the full spectrum of services will have enough bad associations with the name "SourceForge" at this point that keeping it could end up driving away more users than it attracts. And all the time and energy it'll take to rehabilitate the SourceForge brand could just as easily go towards building up some new brand instead, without all the baggage the old name carries.
(It's possible I'm overestimating how long peoples' memories are here, of course. But when I hear "SourceForge" I still think of all the bad stuff they did in the past, so presumably there are at least a few others out there like me as well.)