Taylor Swift signed a deal with a record label instead of being an independent artist because it seemed (and possibly was) advantageous at the time and now that she is rich and famous and doesn't need the label, she no longer wants to hold up her side of the deal (giving the label certain rights to her earlier music for a certain period of time) and so now she is playing victim to get her fans to pressure the label into giving her more generous rights to the music she signed to them.

Basically when you sign with a record label you give them certain rights with respect to creative control, music ownership and licensing in exchange for them investing in helping you produce and market your music to a wide audience, network in the industry, tour, etc. In short, they help you make it big and take on early costs and risks and in exchange you make them rich if you do become extremely successful.