important enough to maintain a local copy backup. tis why I tagged #3-2-1%20ignore you only need the machine on when adding to the archive. Then just shit it back down and leave it alone. Nope.
Regular backup tests is part of backup hygiene.
Otherwise you have duds you need to replace.

You can say it to the C-Suite all you'd like, but Goodluck getting them to budget for anything sometimes. Spinning rust, lto tapes, etc and the software to handle them is generally considered out of budget, at least at most orgs I've worked with (despite the recommendation to practice 3-2-1). Also, you may want to further detail your advice, most storage mediums (save lto tapes) require ongoing power to prevent things like bitrot. It's quite common for hard drives for example to develop bad sectors over time, but algos running on the drives embedded firmware clean this up by repositioning bad sectors to a reserve space. Nvme/flash is even more vulnerable to this and behaves similarly.

Getting hard to find WORM drives & media at an affordable price nowadays. For larger orgs like PBS maybe it isn't such a problem, but for us everyday schmoes...