Giving in to the most demanding person, whether or not their demand is reasonable or fair, can make things quiet temporarily. So does giving your kid what they want whenever they throw a tantrum.
Ultimately, though, they produce the same response - a spoiled, demanding person who makes like miserable for everyone else, and thinks that throwing tantrums is the best way to negotiate.
So from a Boss's (or parent's) perspective, the questions to ask before giving in to a demand are "Is this a reasonable request?" "Is it unfair to anyone else?" "What are the long term repercussions of acceding to this request." and "Is this person in the habit of making selfish demands".
So a request of "I have trouble concentrating when people play music out loud. Can we ask people to use headphones?" could get an easy yes, and a new policy, while "Coworker's music clashes with mine, so tell her to turn her music off when I'm in the office" get a "You've got to be kidding, go away".
And the other coworkers will very, very quickly realize that the most demanding, unreasonable person gets whatever they want, no matter how inconvenient, unfair, or damaging it is, and that can really poison a work atmosphere.