I'm a big tree-chopper who believes that all junk trees and any other trees that infringe on playablility or health of turfgrass ought to be removed, but reading and relying on these quotes from the golden-era golf architects is a bit like reading the Bible and cherry-picking verses. Like everything else in society, the pendulum on tree planting swung way too far in favor of haphazard, tunnel-vision tree planting.
I would guess that the hacking at Oakmont represents the opposite swing of the pendulum. One can only hope that there is a happy and relatively permanent medium that can be reached, but I think it is probably naieve to think that one should "restore" all golf courses to the way they were originally built, especially in terms of trees.
I suppose that some would consult their "WWDD" bracelets and ask what would Donald Ross do? The answer is that Ross allowed the planting of hundreds, if not thousands, of trees during his decades at Pinehurst. He presumably did a good job of locating the plantings.