We have a fire proof safe where we store our backup drive. Better safe than sorry and we don't have to pay a monthly fee to a Marxist pos company.
At on time “fire proof” safes protected paper documents from being destroyed. Paper can take pretty extreme heat before browning/burning. Are the newer safes good for electronic devices and plastic? Those are damaged at far lower temperatures. Another important factor is time. These types of safes are only good for limited time of exposure to fire. If the fire burns long enough the contents are done.
You should keep your computer record on a backup drive, offsite.
Better to have them in two locations in the event of a fire.
I use Time Machine on my Mac . . . but you make an excellent point about physical security. Wonder if there’s a way to use Time Machine to make multiple backups . . .Or maybe I should just get a second drive and periodically back up my Documents file and my photos . . .