An oldie, but a goodie. I recently dusted off my install after ManyCam re-wrote the definition of "lifetime" and screwed over a bunch of its most loyal customers.
Other folks quite like VT-X and TriCaster setups. Or Wirecast, or XSplit (itself notably big in some circles). The only "reskinned OBS" I know of is StreamLabs OBS, which, yeah, isn't great, but there are quite a few alternatives.
On the audio front, I'm not sure calling it "the category leader in audio manipulation" holds much water, given that OBS's audio facilities are notably its weakest point. (Not entirely their fault. The licensing around ASIO is weird.) Voicemeeter plus your DAW of choice come to mind. Or, for live mixing directly in your video mixer--well, vMix and NewTek both are pretty good choices there, too.
This is not to take anything away from the OBS project or team; it's quite good at what it does, and if your needs are in their crosshairs or you're willing to expend as much effort as necessary to build what doesn't exist around it you can put on a great show using OBS. (And in particular I think their game-capture logic is best-of-breed; when running events I still use OBS as an ffmpeg frontend on my satellite systems because I don't have to think about game capture.) But the idea that there are no "real alternatives" isn't correct, particularly when you have more moving pieces involved and you don't want to--or, for less programmery types, aren't able to--spend your days writing duct-tape code around your video mixer.
Linux is a distant outlier in the overall streaming space.
If you’re narrowing scope down to “free and works on Linux” then OBS is your go-to, of course. But Linux streamers are a tiny subset of the streaming target audience and anyone doing this professionally should at least consider some of the paid alternatives.
As far as "free" goes--OBS is great where it fits. It's exceptional where it fits. And if that's what you need, you absolutely should use it. When it doesn't fit, you start getting into build-versus-buy territory, and once you pop the cork on buying you can buy a lot for relatively little.
Why I responded at all was the maximalist dismissal of a pretty large industry of smart people doing interesting things in the video mixing space.
Are you saying that previous lifetime owners only get two years now? By pure luck, I purchased ManyCam the day before the price change.