I think there's a false framework involved here, both in terms of what the R&A and the USGA do and in terms of how we discuss those actions.
For professional golfers, there are well over a hundred tournaments a year on the PGA, European, Asian tours etc. Every single one of those tournaments is held on courses that have already been modernized and updated (whether they are new courses or older courses that have been lengthened and renovated over time).
In other words, the Open or the US Open could -- as two tournaments amongst a hundred every year -- be played on any of those courses, just as they are presented week-in and week-out, with minimal additional preparations/changes. The reason this isn't the case is that the R&A and the USGA believe, rightly I suppose, that the US Open and the Open are not regular tournaments, ie that they are special and unique.
Okay, let's grant that - these two championships/majors are special and unique. The question is, why does it seem that the R&A and (especially) the USGA have over the last several decades only been able to think of this specialness-uniqueness in terms of toughness?
Why the lack of imagination and insight and nuance? Is being harder (i.e. protecting par) the only form of specialness and uniqueness that the governing bodies can think of or imagine?
For courses that have been around for nearly and sometimes more than a hundred years, is being a tough test for the pros the only measuring stick of their greatness, specialness and uniqueness?
Peter