On my first ship in the Navy, we had a Windows 3.1 beige-box desktop PC (well, there were 3 of them, 2 for backups) that ran a tape drive emulator that connected to wiring in a bank of disconnected tape drives/computers (took a whole wall, these were the reel-to-reel kind) that ran some old targeting radar. The weapons that used that radar were gone, but they kept the radar running for auxiliary purposes. I'm surprised they wouldn't use something like that at NASA. We only left the drives installed due to weight distribution for the ship, but NASA could just replace a whole room of them with a Raspberry Pi, probably.
I think NASA (or space industries in general) has the same problems as Navy (or military industries in general), they don't want to change anything that works. Reliability is one of their paramount KPIs, and what has survived for more than a decade is considered tested for a decade and will have precedence for managers in this space.
There’s a lot of places with extremely high data storage requirements that use tapes; they’re fairly dense and fail much better than spinning hard drives (as in, you can just splice out bad tape rather than toss the whole disk).
I should have said "NASA has the specific tapes, dusty decks &C in archive which demand it keep a lot of otherwise dead technology working so it can read specific tapes"