Why is old ben is not a rebel?

Its just the same like Asajj is no Sith ... she was not, she is not, she will never be ... same goes for Ben being a rebel ... "but ST Han has the rebel-tag" ... "but Savage has the Sith" ... ya ... s*** happens ... while Savage we could say he was Sith when i was Darth Maul's apprentice, but there were other 2 Siths (Sid and Dooku) ... so, not sure how if if counts or not ...