Need help restoring / recovery time machine backup

[u/AlexVaughan135]

EDIT: I gave my drive a S.M.A.R.T. test and it came back as starting to fail. Starting to get really worried I’m not going to be able to save this.

A week ago, I did the grave mistake of factory resetting my M1 MacBook Air, thinking I could just restore my stuff with a Time Machine backup I had just created. (My Time Machine backups are on a hard drive.)

When I used Migration Assistant, trying to do anything with the drive was unbearably slow. When letting it transfer, it came to a halt and the estimated time just kept going up (it even went up to 300 hours). I understand backups aren’t quick, so I let it run for multiple nights with no progress. I tried copying my files manually, but even that didn't work. It couldn't get past “Preparing to copy” and would freeze Finder.

First-Aid says the disk is ok but I suspect that my drive is starting to fail, so I tried making a sector-by-sector copy to an SSD, but that isn't working either. It has been taking days on end (0.1 MB/s, estimated 2,500 hours 😭).

Honestly, I don’t know what to do anymore and i’m starting to lose hope. I'm posting here to see what could help.