I think you are 100% wrong.
People evolve in different ways. As in said in the box set thread, I can't imagine Pick being the drummer on Money For Nothing.
No human should have to suppress their own creative needs to suit someone else. If your creativity aligns with Mark's (like Johns) then sure, but if you feel the need to play different music or produce albums then it's totally right to move away.
Pick no longer fitted the loud, heavy hitting rock Mark wanted to pursue.
It's a difficult topic indeed, nobody could be 100% right or wrong here. Should it be this simple, all these people could at least stay friendly to each other. And to me, every story of Mark stopping working with somebody (or musicians stopping working with MK) is more like a marriage breakup gone wrong. With John Illsley again being an exception from the norm. So it's not just creative differences, but musical egos clashing.
There are subjective facts and objective facts. The objective fact is that Mark with the help of his friends and his songs created an independent Dire Straits phenomenon that took over the world, without anybody's interference, pressure from record labels, always having enough new original songs to record, etc.. Complete creative freedom and success, but not a democracy. More like a benevolent dictatorship.
I'd be the first one to dismiss the "superhuman" idea, but let's just not diminish Mark's input into this whole operation. Without the guy, there would be no "A
Mark In Time" forum. And as you can see, Brothers In Arms album happened without Pick and was a blast.
I can't imagine Pick playing Money For Nothing as much as I can't imagine Steward Copeland playing "Every Breath You Take", probably the simplest song he ever played. And boy he did it well! Call it not fitting the sound or creative differences, I'd call it if you happen to work with a genius, try to stay working with him and learn from him until you get fired, or become a genius yourself. Well, somebody tried...