I explain in the post. Here's a copypasta of the relevant paragraph:

"My reasoning for splitting these two processes — restic backup and rclone sync — is that I run the local restic backup procedure more frequently than my offsite rclone sync cloud upload. So I’m OK with them being separate processes, and, what’s more, rclone offers a different set of handy options for either optimizing (or intentionally throttling) the cloud-based uploads to Backblaze B2."