Exactly this. Most of the software others will build with GPL'd stuff isn't interesting to the owner of the original code. They're not doing it to fix bugs. The

Exactly this. Most of the software others will build with GPL'd stuff isn't interesting to the owner of the original code. They're not doing it to fix bugs. They're doing it to add stuff for their own products. No community of the original software's devs is going to want the output of everyone else's surrounding code or customizations.