Not necessarily, generally the defaults for most of the tools tend to be sane, but when you have a swiss army knife with dozens of attachments, you'd still need a manual to figure what is what.
Note that many tools use ffmpeg under the hood so users are generally never exposed to the various options. But sometime if they need to, cheatsheets like these are really useful.
I'm willing to forgive ffmpeg because it can do an insane amount of stuff. It's nice to know whenever I have a weird media related need (converting a file, cropping and compressing a video for discord, etc) that I already have a tool capable of doing it on my machine. Just takes a quick search for the command and I'm ready to go.
To be honest, I kept a text file of all my most common ffmpeg commands in my video folder for quick reference.