For example, this one doesn't document the -B option, which was added in 2011(!):
https://git.kernel.org/pub/scm/fs/ext2/e2fsprogs.git/commit/...
Better man page link:
This used to be my experience as well. However I've had a couple of WD Reds that developed a few (~20) bad sectors, one two years ago the other three. Both have been stable since, and I run periodic scrubs on them.
When the first one happened I had planned to swap it out, but was a bit low on cash right then so waited a bit. Then I saw it didn't deteriorate further so I go curious and decided to wait. Still waiting.
Now if you start getting into the hundreds, then yeah, the drive is dying.
If you're designing something as complex as a drive, you would have thought they'd have a bit of electronics to test the power supply and refuse to work (with some relevant error code) if it's out of spec.
However for deciding if an old disk is still usable I've found that overwriting the whole disks multiple times with the badblocks utility (https://linux.die.net/man/8/badblocks) - if the disk passes multiple runs without generating new bad blocks it's often still usable