dcmg
As so many others have pointed out, SONAR never really had the "pro street cred" of PT and others.
Financially, Avid conditioned its users to a cost of doing business that was higher and reinforced that notion that this is the cost of playing with the big boys. Pros and novices alike bought into that.
One of the things ProTools has/had going for it goes right back to the early days of DAWs sufficiently capable of replacing tape-based systems.
It offered, at a price, a combination of hardware and software that would be certain to work together. It worked with external ADAT-based hard drive recorders such as the Alesis HD24. They were thought - whether correctly or not - to offer protection against a studio owner/manager/accountant’s nightmare of recording the clients then having a computer crash that lost data. And all this was supported, at a price, by a dedicated help team and engineers who knew PT and the PT approved hardware very well indeed.
It also interfaced with existing analogue and digital hardware and basically offered a simiar paradigm to tape but with the added copy, cut and paste editing functions of digital so the razor blades and sticky tape could be slung in the bin and forgotten about.
A combination which made it relatively easy for PT to become a studio standard. Not because it was “the best” at everything, or even the best at anything, but because it removed a big bundle of uncertainty about new-fangled computers and new-fangled multi-track digital recording. And once the capital, testing and training time has been invested the tendency when considering an update is to go with the latest from the company you know.
Once the “big boys” in any industry are seen to be using something the lower reaches tend to look to the same stuff. If the leaders have tested it all out and are happy with it, then for a smaller business buying the same stuff saves on an awful lot of worry. And the customers read up on what the top studios use, and again assume that using a studio that has the “industry standard” is a wise decision, because it’s the “industry standard”.