Did anyone else lose all of their saved games with the 1.59 update? I was going to restart anyway, so it wasn't SUPER critical, but I'd hate to lose everything again!!!

Not here. I do always make a backup of the save-game directory before accepting a large patch so that may frustrate Murphy the Trickster God. I was able to "play through" without any drama.

Are all of your save slots in the initial game select menu empty? Do you have any files in the save directory at C:\Users\YourNameHere\AppData\Roaming\HelloGames\NMS\DefaultUser?

Sorry to hear. Only explanation I have is: you have uninstalled the game and during this you answered YES to the question to remove your savegames. You should not :(

But:
Go in the savegame folder, right-click on it > Properties > Older versions
and you should be able to re-copy older saves, but this assumes that the Restore options for your drive are enabled.

Else, pardon, but you need special recovery software :(

I just ZIP up the DefaultUser directory and save that somewhere. Restoration should be nothing more than unzipping and overwriting any existing files.

Except -- the GoG cloud backup of your saved games will have newer timestamps than what's restored from the zip.

What backup do you have now? Assuming you have one, what I'd do is to zip up the current DefaultUser directory (just in case) and save it. Restore your backup files under DefaultUser.

Then unplug the PC from the network. That prevents GoG from attempting to "fix" the out of date files. Start NMS and check that the saved game you want to run is viable - everything loads and behaves correctly. Do a new save, which will update the file timestamp (and any internal timestamps), and exit NMS and GoG. You should be able to reconnect to the network and launch normally.

I don't think you have to be so drastic as to physically unplug the router/modem. Under settings in Galaxy, disable auto syncing saves with the cloud, quit Galaxy and relaunch (just to make sure the setting has updated), copy your backed-up saves into DefaultUser, launch NMS, make a new save in game to update the timestamp as you said, then re-enable syncing to the cloud.