SOE owns the rights to that system (via copyright), they could use it again in another MMO. Why would they give it to a competitor? This would mean that BioWare would have to reverse engineer (pardon the pun) SOE's crafting system and then figure out how to incorporate it into the current SWTOR crafting system. Neither of which is easy by any stretch of the imagination.
I agree with most of your post, except this part. There was nothing magical about the SWG system. No reverse engineering needed. It was a crafting system and it worked a very specific way and was far from perfect, itself held down by legacy development that never got re-engineered.
It's not hard to design a crafting system just as complex and probably better, on the other hand to actually implement it is quite a bit of developer time, especially coding.