No one actually answered this so:
What it actually mean is; if you've created a backup wallet.dat 6days ago (approx), you can still restore it to you Bitcoin Core with 2GB pruned blockchain.
Any older backups will require you to rescan blocks that are already pruned so it will not work without downloading the blockchain from start.
(you'll be prompted to -reindex if you try to load/restore an old backup)

So if you intended to restore an wallet later, it'll just be a waste of time.
If you want to do that, load the wallet before starting to download the blockchain.
If there'll be no wallet.dat to restore, then it's good.