It is. GeForce Experience will stream to your predefined YouTube or Twitch channel just by hitting ALT-F9 (or whatever you want it to be), among other programs that do similar.
People choose to use OBS for the extra features. Scenes, layouts/overlays, embedded interactive features, etc etc.
Because, even for small operations, you want to make it yours. And making it yours involves a lot of creative decisions. The software has to support those creative decisions.
I use vMix to do single-camera personal streams and five-camera, eight-feed, we're-adding-a-drone-soon fighting game tournament productions. But that's because I've already bought into the complexity enough to do it (and the budget; my copy of vMix cost $1300).
I'm not sure I see much of a market for XSplit or Wirecast, but they've got their fans...
Check out Streamlabs OBS (SLOBS), its interface is much more streamlined than regular OBS, though they still have some difficulty walking the line between flexibility and simplicity.
There are tools like XSplit which make the process simple. Of course, said tools are Windows only, since the target audience is gamers.
If there's enough of a market for simple code livestreaming, then the multiplatform tooling will follow. (or someone could fork OBS like what Streamlabs did and strip down the features).