Just my opinion, but...
RS is pretty independent. Once he forms an opinion, he'll tell you what it is.
What he makes writing probably doesn't keep him in primers.
He doesn't suffer fools gladly.
He writes about what interests him now. I don't remember him cranking out any recent articles about something he researched ten years ago. There are some writers who have made carreers out of the same six articles.
I'll hate to see him go, and will be buying fewer Wolfe mags in the future because of his departure.
As far as other writers opinion of him...well, writers, like lawyers, plumbers and mechanics, seldom have anything good to say about their competition.