Sorry to be that guy but replicating / syncing isn't really backing up.

You need snap shots or versioning.

Yep, hence my comment...

You should see the fear on people's faces when I suggest they restore a backup - esp. on Production.

My advice (to combat their fear) is to take an offline backup that has some kind of checksum and then immediately restore it.

That gets them past the initial fear and then we progress onto other backup strategies... if needed.

Yes, and keep a copy offsite! A good friend’s house burned down in the recent Eaton Canyon fire. He and his family lost absolutely everything. Photos, letters, memorabilia — the story of their lives. A devastating loss. He had plenty of backups, but none stored elsewhere and the ones in his house were also thoroughly toasted. Friends are working to find copies of photos, but that is just a fraction of what was lost.

It isn’t hard to do backups, just a chore. I by a thumb drive every few months. A few terabytes is not too expensive and it is small. I backup to it and mail it to a family member. I know it is safe. Daily backups are better but more cumbersome. I back up weekly to hosted disk drives at a small Internet service provider.

It isn’t hard to do backups, just a chore

Right, and since now we have devices that can store thousands of pictures and data, and SSD cards that do the same, people tell themselves, maybe later, later, later until later catches up with you and you loose everything. It's been at the end of last year, but my lady friend was riding my ztr and her phone fell out of her pocket. Next thing I saw was iphone bits blasting out from under the mower deck. Now luckily, I am very fastidious at backing up her phone, but shit happens and I've always been one who adhered to the 3-2-1 rule. In fact, on my daily driver computers, the only thing that is on their HDD is the OS, and maybe a app or two that I wanted to check out. They really are like thin clients. Otherwise, everything goes to storage and that is backed up daily.