tldr pages are a great idea, but the execution is a total fail. Looking at the rsync entry, it fails to provide the most blatantly common requirements:

I just needed two commands: one to mirror a folder from one drive to another, updating only the changes (excluding all of the hidden MacOS cruft). And another command to do a deep validation of the copy. These have to be two of the most commonly used commands right???

In the end, I felt that messing around with precious data without being 100% certain of what I am doing just wasn't worth it so I got a GUI app that was intuitive.