Question
I'm on limited internet. Now games are so huge, I was hoping to download them once, then back these up on my NAS using the built in backup function. Then in the future, instead of downloading the whole game again, I can just restore the backup then allow steam to download whatever patches have been released since I backed up the game.

This is how I assumed the backup/ restore function would work. When I tried it this afternoon though on 4 different games: midnight suns, metal gear solid 5, battletech and baldurs gate 3 (yes all 130GB of it). The backup works fine. I point steam at my NAS and it creates a folder for each game with multiple 1GB archive files in there.

If I then delete the game from steam, and try to restore the backup. Steam just downloads the whole game again. It doesn't appear to use the backup files at all. What is the point of creating 100gbs of backup files that steam then doesn't use?

Had anybody managed to get this very old feature to work? This is not the same as network transfer. I don't want to transfer the files to another machine with steam installed, I just want to back them up on my NAS. I know you can copy/ paste the steamapps folder. I just want to know does the backup/ restore thing actually work or am I simply wasting my time trying to use it?