From a friend that was a roadie for them in the very early days, he has never played without effects (when I saw them in early 1980 he was running through a lot)
I suspect that he has, as you say had to carry the band so much that he hasn't had time (or inclination as things have worked out pretty well for him so far) to look for any sort of natural tone.
I wish I could be kinder to him as he has done well for himself, but his sounds makes me spend more time wondering what effects he is using rather than paying attention to what he is playing.
Addition : After finally getting the whole way through the clip I have to say that if anything he is hiding the guitars tone more than ever, frankly you wouldnt have known that was even a 12 string he was playing at the beginning of the clip.
Still I wish I could have gotten to where he is (instead of working in the IT business and bitching about him, in my case)