In 2001, I created an open source Verilog code coverage application called Covered and hosted it on SourceForge due to its dominance in open source hosting at that time. When it was time to start TKE about 10 years later, I stayed on SourceForge because I was familiar with its capabilities and GitHub wasn't really a big deal like it is today. These days, I keep it on SourceForge because I have some development workflows that are dependent on my SourceForge setup.

Don't worry, TKE has nothing to do with BitCoin :)