The conversation you have pointed out was from a little over a month since SpongeAPI was first created.
The team has evolved, and opinions changed.
You will not be finding Premium plugins for Sponge outside of commissioned plugins. We of course can’t control what others do, and our license doesn’t forbid commercial use or linking of commercial use, so of course resources outside of SpongePowered can’t be controlled, it’s just common sense.
But you wouldn’t want to be caught doing it if you want to remain in the good graces of the individual team members.
We however do endorse that people be allowed to be paid for their time if developing something custom, we just ask that aside from our sub-forum for devs wanted / developers listing their services, that everything to do with payments / settlements / contact happen in private. As we do not want to deal with the fallout, do not want to provide a medium for drama to foster, and believe that outside people recommending peoples services, that visible discourse of the details would cause trouble.