You don't have any backups at all if you never tried restoring and testing them
If it's your personal stuff, skip it at your own peril. If it's a paid responsibility, that's what hourly billing is for (this incentive was much stronger when I learned netadmin, back before nvmes)
Doing it on a second computer wouldn't have caught this problem either with macOS 26.3 and earlier, because it was introduced in 26.4.