Not sure I am following this. Did Google release this because PG backups are not 100% reliable or the data corruption can occur due to hardware failure.
The rule of thumb is you should verify that your backups can be restored before you consider them reliable. You don't want to end up in a disaster recovery situation and find that your backups have been corrupted in any way shape or form. Many things can break your backups, especially if they are automated and have many steps involved.
One way to do this is to actually restore the data on a different system and compare. This tool appears to do the comparison for you directly to the dump, increasing confidence that it is reliable.