It was the go-to for hosting small projects for a time, back then.
What made it unviable except letting it languish and then shutting it down?
It had what was essentially an HTML4 UI and just SVN support for what seems like forever. I can't remember a version of it that didn't look like 2005 Gmail.
Hence "languish". When it was first made available in 2006, it wasn't an also-ran.