Tape ages badly. It can get so flaky that if you unwind it fast the oxide sheds and then clings to the head. Heat demagnetises and also warps the substrate. And then there's print through where sound on the next wind (above and below) gets imprinted into the signal. Old tape wants reading with as few moving parts as possible. I went on a tour of the British Library where their archival engineers talked to us about advanced preservation. Unwind the tape very slow onto new precision reels. For desperate cases it can be re-coated (sprayed) to stabilise. Then the trick is to use a low or zero-contact head. There must be some good tape engineers around who would still do this for a price or love of a recording.