You are suggesting you no longer have what you purchased first with destiny. Which was the story, strikes (normal ones) and crucible. As far as I know all of these things are still accessable to anyone. Now things they have added, that you did not originally purchase is the raids, nightfall, dlc stories, and dlc gear. A more precise analogy would be I bought season one, season two has come out and I must now buy it. It is not included in the season one purchase. Long story short what you paid for originally is still there. Everything you purchased prior to the taken king is still there. If you did not purchase any dlc then you will only have what was originally in destiny as stated in the first section.