I've written about this on here before, but if you believe everything in GCA is subjective then you are accepting that person A's view that Dogtrack Muni is a better course than Cypress Point has validity.
I don't believe that. Meaningful judgements of quality can be made in spheres that ostensibly seem subjective; they are in literature, music, art and so on. They are made by combining the considered opinions of qualified individuals to produce a canon. The canon doesn't have the status of fact; it just represents the best assessment that is available to us at the moment, and it's subject to refinement and even overturning if a future voice convinces informed opinion of his case.
This is pretty standard critical theory, and I don't see why it shouldn't apply to assessing golf courses.
On another theme, I don't know, because I haven't inquired, how any of the major magazine rankings are calculated from the piles of individual ballots. But mitigating the issues of regional bias, small samples and so on is not hard to do, using fairly basic statistical methods. You can give each voter a weighting, based on criteria such as the total number of ballots submitted, the geographical spread of those ballots, etc. You can depreciate the value of a ballot over several years, before finally eliminating it. The magazines may be doing this; I don't know.