All of the cli programs you use might have perfect, modern apis, but the issue is that the breadth of your workloads means that you can't memorize every cli program api across every case that pops up.
Consider any program or arguments you seldom use. Or come up with an api for ffmpeg that you think is optimally approachable and you'll see that it's so full-featured that you aren't going to keep it all fresh in your head when you use it every few months.
Consider any program or arguments you seldom use. Or come up with an api for ffmpeg that you think is optimally approachable and you'll see that it's so full-featured that you aren't going to keep it all fresh in your head when you use it every few months.
I'd rather let the computer do grunt work for me.