Upgraded yesterday to 9.2.18 and 20.2.4, then ran through the process successfully. Relatively simple 3-node cluster. My only gripe is that in some cases it wasn't 100% clear if I should proceed, since the script didn't have the nice green PASS...
It is not the same. You have e-mail for every (of some type) job. Possible many e-mails.
When you backup from PVE, you have summary. But separated by jobs and even by nodes. Many e-mails.
If you backup some systems by filesystem agent...