Imo it's the opposite. Learning to use FFMPEG feels like overkill when OBS makes simple tasks simple.

Good luck figure out the command to compose even a simple scene with a webcam on top of a desktop feed, let alone switching inputs or mixing audio. All of which are very basic thing you'd want to do when creating a screen recording. Meanwhile it's 4-5 clicks in OBS.

Well most obs users like the facility of composing scenes without having to check how to identify each window/input/source. I tend to favor cli tools but we are talking about video software and the ability to have immediate preview is really comfortable. Also I don't think ffmpeg can switch scenes comfortably. I am using obs to create some video tutorial at work. I could record different rushes but I find it more convenient to record a single rush with different scenes and cut the hesitations or repeated moments due to bad prononciation or cough or whatever afterwards with avidemux.

However this give me an idea about a tool that would export scene composition and video output settings to ffmpeg argument for easy reuse. It is true that if you don't have an usecase where you switch scenes it could be handy to start a record/stream from a command line. For example I have been ripping some videos from my streaming services so that my daughters can watch the movies on a plane, works great for that. Didn't bothered using ffmpeg because the preview allowed me to be sure I was recording the correct window without realizing 2h later I had recorded trash. Surely there are better ripping tool but at least this way probably do not attract attention from said streaming services as you are recording in real time.

I'd love to see the one liner for ffmpeg that actually does this. You could probably publish it as a novel, haha

I love ffmpeg as much as the next nerd that tinkers with video but.. it's video. It's so much nicer to interact with it using a GUI.

Not to mention if you did something wrong you could just change it in OBS rather than kill the stream and tinker for half an hour

Low latency hardware encoding and muxing with ffmpeg can be rather tricky depending on your setup. OBS works out of the box on every platform. If you’ve never measured end-to-end latency, your viewers are missing out.

FFMPEG also requires a command line which makes it completely unusable for nearly everyone.