It reduced size of backups when I moved to restic snapshots. Before restic I archived the files and pushed them to s3 as well. It was time consuming and inefficient, it created copies of files in archives. With restic I keep last 30 snapshots, I take them every 12 hrs, it means I have snapshot of last 15 days and backup size is less than what it was when I was doing it without restic.
example cron / script you will have to run.
# Switch working directory to frappe-bench
# backup db only
bench --site all backup
# list previous restic snapshots or init restic
restic snapshots || restic init
# backup files including db dumps
restic backup sites
# cleanup snapshots
restic forget --group-by=paths --keep-last=30 --prune