I wasted a good chunk of a day looking into this. If you start multiple instances of OBS (you need to do this on the command line otherwise clicking will just foreground the current instance) then "multicording" should work fine, though perhaps using lots of system resources (the fan goes nuts). This was on macos.
Overall, I realized it's better to just use OBS and have it mixed into one file/stream. You trade off a bit of flexibility to do after-the-fact editing but save a lot of production/editing time.
It's not better--you're just not paying for tools that do it. When it works it solves entire categories of problem and it's one of the reasons I pay a lot of money for vMix. (In fairness, the OBS developers I know are super sharp and I'm pretty sure that this is somewhere on their to-do list.)
Overall, I realized it's better to just use OBS and have it mixed into one file/stream. You trade off a bit of flexibility to do after-the-fact editing but save a lot of production/editing time.