I found discussions in the old forum dating back to 2013 and 2014, while I was searching how to limit a Virtual Assistant's access to delete content on my site.
The Chat Support person said "it's on your radar"
Something on your radar for five YEARS tells me that SS does not consider it a priority.
This is not acceptable.
When is Squarespace going to offer the ability to backup our site, or roll back to a previous version, or recover lost content? Yes, I realize storing indefinitely is not realistic....charge extra for it...I would gladly pay for "website insurance". For standard users, maybe offer a limited 30 day roll-back period included in the subscription. Something!
And, prevent this further by adding a User Permission that restricts contributors to specific tasks (can only add pages, can't delete), and/or specific areas (can only add non-linked, not pages that show in the navigation ; can only work within the Blog area, not the Pages area, etc).
To me when i saw that this has been under discussion for so long, I had to say something. Somebody up there at SquareSpace needs to hustle up, buttercup!