Quoted Wisdom, Quotable Quackery
Quotes are selected, often general, and commonly removed from context, meaning you can quote whoever you wish, it cannot add to evidence of a claim unless it's from an expert in that area of knowledge and hasn't been surpassed since it was stated.
In other words, wisdom is overrated; quotes are biased by definition. The simplification of concepts is not an outright error, and in such cases the definition is incomplete. And this is including popular scientists, who will make an explanation easier to understand, then others will use this simplified version of the facts, people love to use these as if the intellect is a point scoring system. They'll select diluted ideas that seem very talented and may have a philosophical quality, even if these quotes will likely lack nuance. In many ways, wisdom is not the work of explaining but the art of personal understanding, in which case wisdom is subjective, inspired by possibilities in a way that gives pause for thought. And a fool may find inspiration in the unreal just as a pure intellect can find nothing there but the puzzled thoughts of lesser minds.
The best examples of quotes are often pseudo-scientific, the quacks use selected factual quotes or those from scientists to support an unscientific series of opinions. And clear the goal is often to fleece the convinced once you have developed a following. These shameless entities leach onto the hunger for knowledge that most of us enjoy, they trick the somewhat ill-informed and make a business from a half-baked philosophy. In fact, the lowest blow is where a person clear has originated the deception, so rather than accepting an inferior authority, they have gone through the various statements of a respected historical figure to winkle out a few choice words. This can be to support or dismiss claims, as with the criticism of atheist authors, although, this is often applied by amateurs and on either side of the debate. Where they dishonest can use a statement to support or defame a person or idea, they will likely do so.
A person wishing to misrepresent a position will select quotes and even those cited by the person they debate, as happened in one instance of a debate between William Lane Craig and Sam Harris. Dr Craig used selected quotes that Harris had quoted from others and were not his position. And to those who aren't interesting in context, it seems to be a refutation. This kind of misrepresent is common enough, in my opinion, it's the lowest form of debate since a dishonest selection process is used to discredit the individual and not to deal with the factual arguments. I don't doubt that many sceptics would do the same to discredit their opposition in a debate, although, if we are honest, we should point out these errors regardless of who uses these methods. What matters more than spin is the facts, their meaning and context, and who passes on the facts isn't as important.
The best quotes are those that hold meaning, not those from the famous and wise, and most quotes are just ripe cherries that you pick them from where you can and use them you will. Relying on quotes, sayings and parables, or anything you take from the world, is ultimately meaningless if you fail to think for yourselves.