Why is my snapshot's size smaller than the Droplet's disk usage?

While snapshots provide a complete copy of the Droplet’s disk, snapshots are compressed when we store them. This is why you may see a discrepancy between a snapshot’s size and the Droplet’s disk usage.

When you spin up a new Droplet using a snapshot, it is important to confirm that all of your data is present before deleting any other existing copies of the data.

No, you cannot downsize a Droplet using a snapshot.
You can recover your Droplet if you have taken a snapshot of the Droplet or signed up for automated backups.
Destroying a Droplet destroys the backups along with it. You’ll want to preserve your backups first.