For me, the worst thing to rank are wines, but that has minimal impact on most of us. I also think "we" tend to misuse rankings, "we" might think a university ranked 40th is better than one ranked 50th by USNWR, putting aside whether those rankings are any good. I use them for two reasons:
1. To spot something I didn't know might be pretty good, like a university I never heard of that was ranked say 30th.
2. To get a very general idea of which schools have better reputations, not 1 v 3, but schools in the top 20 probably look good on a resume.
A wine ranked with say 90 points is not worse than one ranked with 92 points necessarily. It's a tiny tiny difference judged by, usually, one person using his criteria.