Mark,
For my part, I think today's overall system of trusted constructor (LUI, Wadsworth, others) has largely helped architecture, in several ways. First, courses are just built better. One knock on Pete Dye courses, for instance, using largely inexperienced personell is that they were generally not built as well as some others (I am just reporting what I hear in the industry....)
Secondly, as shapers move from a Fazio job to one of mine, or vice versa, they tend to take the best of both worlds with them and incorporate them. I could give you a few very specific examples of where trends of each of us has been put into the others courses, and IMHO, to the benefit of both. Its not that we gca don't study all the best works over time, but it also helps if the bulldozer guys who actually build them study them to, and most do.
I know Tom Doak will argue that they should only study the classics in GBI, and that certainl helps (I know Perry Dye for one took all his shapers to Scotland at least once) but there is a lot to transfer between gca's both technically and artistically and that has tended to bring all courses to a more similar level. Whether that is a blandness is a matter of opinion. Maybe, if we see some of the same trends in too much work.
Frankly, I have also heard whispers of "sameness" for the darlings of this site who use their own crews mostly, starting to be heard, because they have done enough work that most folks are saying "we have seen this before" much like they said it about RTJ and others in earlier days.