One final thought and then I have to go: I think there’s also a perception issue here which comes from the fact that Steinberg is very careful about OS updates.
They had the big disclaimer up not to use Windows 10 all these months, but in my own tests there were no issues, so I jumped on it early. Working ten hours a day on it, it took me weeks to even notice what it was they were warning about, and then it was really easy to work around until Microsoft fixed in on their end. Similarly, C8 works on my MacBook Pro with El Capitan just fine. I have no idea what the issues are, but the MBP is not my work computer, so I could’ve missed something. So do NOT take my word for it.
But I think some other DAW companies would probably just say “oh well” and add the new OSs on the list of supported systems and just consider the issues like any other bug. I think people are aware of that and probably don’t update to El Cap before a critical session with any of those programs. At least I hope they don’t.
However, it would help if Steinberg communicated a little more clearly what the actual issues are. It’s good to give the overall “don’t use it yet” warning, but people who are more eager to check out the new OS should have a better idea of what they should expect not to work. The general doom and gloom warnings make it look like Steinberg’s software completely breaks every time, which is not true.