I just had someone go through an aspect of my 4 generation tree and change a bunch of names and dates that weren't even close to being correct. All these changes were done by the same user and they weren't even close, it was taking verified birthdays from 1800s and changing them to 1900s and moving them from birthplaces of Denmark to Scotland. These were on family members whose work had been done and all have 20+ sources showing their name and dates as being correct. It happened to about 10 people in my tree. If there was a way to lock changes from being made with something that has so much source evidence backing it up that it couldn't be changed until close kin (who are active on FamilySearch) could "approve" those changes. Especially on ones where the temple work is completed.