I thoroughly backup up my slow nvme before installing a new faster one. I actually didn’t even want to reuse the installation, just the files at /home.
So I mounted it at /mnt/backupnvme0n1, 2, etc and rsynced
The first few dry runs showed a lot of data was redundant, so I geniously thought “wow I should delete some of these”. And that’s when I did a classic sudo rm -rf in the /mnt root folder instead of /mnt/dirthathadthoseredundantfiles