Without having details on the specific floppy disks in question there’s no way you can authoritatively say they are unreliable. They absolutely produced floppy disks that were far more reliable than the ones sourced from the cheapest vendor possible some of us used in school back in the day. Ignoring the fact I’m guessing the disks in question aren’t having to survive life in a students backpack.
One cost $100 another $1.
Then these tapes are typically write once read many.
They were designed to deal with floppy disk flaws consumers deal with.
Actually really cool to read about modern tape systems.
We switched them over to external USB enclosures with cheap SATA drives in them and never looked back.
Is it because "long-term archival" strategies aren't updated frequently?