Interesting article, Michael. Your most pertinent comment is near the end, 'most buying decisions will be made around lens mount and legacy glass already owned rather than anything else.' I am a mere mortal with a finite bank balance. Having spent lots of money on good lenses over several years, the thought of getting rid of it all to replace it with similar just because of buying a body from another manufacturer makes me shudder. OK, there are probably adaptors, but do you have the full range of features that come with good glass and a body from the same manufacturer?
Yup, I am in the locked-in fraternity.