A college diploma isn't a perfect indicator of intelligence, at least according to my own personal belief. There are some graduates of big-name colleges who basically got in on the family name and just wait for the world to come to them. There are people who got in on an athletic scholarship and had a simple path laid out for them so they would be eligible to play. Conversely, there are small-college graduates that bust their butt harder than any Ivy Leaguer, and there are people who drop out- or never even go to college at all- not because college was too difficult but rather because they've progressed far enough already and had enough early success in their chosen life path that college would actually be a hindrance, the class and homework time taking unacceptably large chunks of time away from their job.
But what I am concurring with is that a degree is a reasonably reliable certification that you've at least done something to earn it, that you've done your share of scratching and clawing in order to get your hands on a sheepskin. That is, of course, assuming that you actually attended that college. Honorary diplomas are another matter entirely, and treated as such. While theoretically a college would hand an honorary diploma to someone otherwise unconnected to the college that has accomplished something in their life that has done the college proud anyway- discovered something, invented something, rose to a certain position, something or other that's very meritorious- in practice, sometimes they get handed to whoever it is that showed up to give the commencement speech, or somebody who has met the high academic standards of giving the college ginormous sums of money. You will note an example of this kind of degree on The Colbert Report, via Dr. Stephen T. Colbert, DFA. Colbert has an honorary doctorate in Fine Arts from Knox College in Galesburg, Illinois... a byproduct of being their 2006 commencement speaker. (It is considered bad form to actually call yourself by the doctorate you're given with an honorary degree.)
For a more extreme example, though, let us examine Elena Ceausescu, wife of Romanian dictator Nicolae, who ruled from 1965 until their overthrow in 1989. Elena was born in 1919 to a rural peasant family, barely finished elementary school, got a laboratory post solely due to her brother already working there (it wasn't a very good lab), and was in the middle of bouncing around low-level jobs when Nicolae rose to power. She was the Romanian equivalent of someone in America who'd dropped out of the Mississippi K-12 system, got a poor homeschooling, and wound up working at half the businesses in town for about two weeks each. That changed, on paper at least, when Nicolae took over, and Elena suddenly got delusions of grandeur that Nicolae was happy to feed into. It will sometimes happen that dictators, or the immediate family members of same, will bulk up their personal title to outrageous ends.
Elena was no different. In her case, she started racking up academic titles, on the theory that maybe that would change her image for the better. She took some night classes, eventually being expelled for cheating, but wheedled a doctorate out of it anyway due to the time-tested tactic of locking the doors to the oral examination room, giving potential witnesses the wrong time for the exam, and having Elena send her thesis defense on tape so she didn't have to actually show up.
She took every opportunity to add another accolade to her collection, which included not merely honorary degrees- something that was demanded of every foreign nation she visited as a condition of her deigning to show up- but also an assortment of other titles and positions, and even citations on genuine scientific literature that, in reality, she almost assuredly couldn't even read, her thesis paper among them. On her 60th birthday, a two-day celebration was held in which she was bestowed a variety of titles such as "Prestigious Contribution to the Evolution of Romanian Science, to the Cause for Peace and International Cooperation" and "Leading Fighter of the Party for the Glorious Destiny of Romania".
The United States was not immune from this, though steps were taken to limit the damage. When Elena arrived in the US in 1978, as per her way, she demanded a degree from not just a university, but specifically a university located in Washington DC. That, she was told, she wasn't going to get. She was made an offer, but it was an honorary membership in the Illinois State Academy of Science. They were the only ones in the country willing to go through with it; nobody else would even recognize her. Elena wasn't happy, and not just because she couldn't even pronounce "Illinois". Her response was, "Come off it! You can't sell me the idea that Mr. Peanut [then-President Jimmy Carter] can give me an Illiwhatsis diploma but not any from Washington. I will not go to Iiillllliiii whatever it is. I will not!"
She went to Illiwhateveritis. She could take that or she could take nothing. She was similarly rebuffed in the United Kingdom earlier in the decade when, instead of the Oxford and Cambridge degrees she wanted (as well a a Fellowship of the Royal Society), she instead had to settle for Central London Polytechnic and the Royal Institute of Chemistry. The countries willing to give her the degrees she was originally requesting tended to be the nations Romania was politically aligned with in the first place.
This obsession with academic credentials extended even to the, let's be honest here, kangaroo court that served as a pretext to Nicolae and Elena's execution in the 1989 revolution. According to A Treasury of Deception by Michael Farquhar, when the most serious charges of genocide and corruption and living in gross inequality to the rest of the nation were read to the Ceausescus, they weren't even responded to, but when the prosecution went after Elena's academic titles, that's when they got frisky. One utterance of "the so-called academician Elena Ceausescu" was enough to set her off. "So-called! So-called! Now they have even taken away our titles!" Nicolae protested, "Her academic papers were published abroad!", to which the prosecutor asked, yeah, I'm so sure, who was your ghostwriter. Elena exploded again. "Such impudence! I am a member and chairwoman of the Academy of Sciences. You cannot talk to me in such a way!"
Elena was failing the final test of her life. They're about to take you out back and put a bullet in your head, thereby, among other things, putting an abrupt end to your days in the Academy of Sciences, and there isn't a whole hell of a lot you can do about it. Oh, yes, they CAN talk to you in such a way.
You'd almost have to be a job-hopping rural peasant that barely graduated elementary school not to realize that.