Yes, you do need to ensure that your backup media are still accessible.
Organising an office move at a very large mainframe user several decades ago I discovered a large stack of punch cards at the bottom of a filing cabinet. On enquiring I discovered that it was a vital back up for the mainframe operating system. Pity we had scrapped the punch card readers just a few weeks earlier.
With the present pace of change things become redundant far more quickly.