Pro Tools has the most powerful brand name in DAWdom. Among lay people, 'Pro Tools' is the generic term for 'recording on a computer'.
I would love to see a breakdown of sales for the various versions of the various DAWs that more or less compete with each other, by OS/platform. Would also love seeing what upgrade patterns were like. (Well. 'love' might be overstating things... but I'm interested in this stuff.)
It seems unlikely that CW would do the integrated-hardware thing only. But it's not just CW, it's also Roland, and they specialize in that.
Hardware integration offers a kind of consumer 'lock-in' that software alone can't. It produces a different customer relationship and a different business model. It can be difficult to bridge the two models.
The VS Studio line is an effort to do that. It also functions as a port, of sorts, to the Mac, especially for those already using integrated systems.
Based on what we can see from the outside, the problem CW has is that its top of the line product is software only and is showing its age. It works fine, and you can do great work on it. But as standalone software, it will increasingly drive an upgrade model, based on existing rather than new users. That isn't sustainable.
The combined business and technology environment that CW operates in has drastically changed over the 15+ years that Sonar has been in development. So have the decision-making criteria for those just starting out, whether they think of themselves as hobbyists or as low-budget pros. Existing upgraders are a different story. But not all of them will stay on the train forever.