Crimson Longinus
Legend
Because it is still something that could be created via PC creation rules, or close to it. It is an approximation for the ease of use.Then....what are we even disagreeing about? If you're willing to make those changes, then you're pretty much saying class progression isn't actually binding for NPCs. And while there are a lot of related subtopics in this thread, that point is certainly one of the main ones.
In another thread on the same topic one person brought up an example of some monster drow having superior ability to use poisons than what a PC could even via feats or class features ever acquire. Yet drow are playable species. This is the sort of situation I would want to avoid.