Most of it was digitally archived already so it's not as big a deal as the article makes out. And the analogue tapes were never going to survive more than a hundred years at the outside no matter how safely they were stored so those originals would have been lost eventually anyway.
I suspect in most case of re-issues 'going back to the original master' means going back to the digital copy of it. Which also explains why all the master tapes were sat in an old warehouse on the back lot with no fire protection. No-one needed them anymore.
Current Lash Up:
TEAC VRDS 701T > Sony TAE1000ESD > Krell KSA50S > JM Labs Focal Electra 926.