There are many kinds of attractive attributes of people. Some of these attributes, such as height, youth, beauty, or strength, are relatively easy for most anyone to observe. Other attributes, such as cleverness, insight, or artistic judgment, are harder to observe. In particular, people who have such hard-to-see attributes can usually better discern those attributes in others.
If this were the end of it, hard-to-see attributes would just be less valuable, all else equal, in attracting mates and allies. After all, hard-to-see attributes would then only be useful in attracting people with similar abilities, and those similar others would on average have more options.
But this analysis misses the possibilities of prestige and status. Social institutions can let people translate their hard-to-see abilities into much easier to see prestige and status. For example, other smart people might certify you as smart via an award that everyone can see. So we should expect people whose best abilities are hard-to-see to focus more than most on achieving prestige, while those whose abilities are easier for all to see to focus more on just directly showing off their abilities.
This roughly explains, I think, an important part of the variation in who cares more versus less about degrees, awards, etc. From a conversation with Helen Yang.