The more general someone is, the more cost specificity has, because there is more to be specific about. So people reach for words that describe generality. The

The more general someone is, the more cost specificity has, because there is more to be specific about. So people reach for words that describe generality. The problem is that a word like tall, though general, isn't specific enough to be accurate. Different communities have different ideas of what tall means, because the height distributions are different. Full stack means there exists a stack for which the person who claims to be full stack has expertise across the entire stack, but since different companies have different stacks it isn't clear what exactly that means except that describing it another way would presumably take more words. It tells you something true about them, but does it in a way that has a lot of error. That might seem bad, but it isn't. In communication there is this idea of progressive revelation. If you were sharing the shape of the world, you start by calling it a sphere. As greater interest is shown you proceed to pointing out it isn't actually a sphere, but an ellipsoid. Still greater interest leads to revealing that it is actually an irregular ellipsoid. Only if they are interested in getting more specific do you venture into talking about the irregularities of the mountains and the canyons. The full description of the shape isn't realistically shared - you live on the Earth, but you don't know its shape and if you ever tried to articulate it a stray gust would move a sand dune while you weren't paying attention and you would still be wrong. Someone who is saying they are full stack is like someone calling the world a sphere - it is true to a point, but needs elaboration to produce a better understanding.