which calc feature allows multiple users to suggest edits while preserving the original data

The Calc feature you’re looking for is Track Changes / Record Changes , often just called “Track Changes” in LibreOffice Calc and similar spreadsheet tools.

This feature lets multiple users:

• Make suggested edits without overwriting the original data.

• Keep a log of who changed what and when.

• Later accept or reject each change so the spreadsheet owner can preserve or restore the original content as needed.

So, to directly match your question, the Calc feature that allows multiple users to suggest edits while preserving the original data is Track Changes (Record Changes).