The problem with long skill lists isn't just accessibility, but that even from the PoV of what they try to embody they make NO sense. They're invariably endless variations of the same type of action treated as separate abilities, so that if you master one skill, but not another that's basically THE SAME FUCKING THING (but a different vehicle or type of melee weapon), you're inexplicability completely and utterly incompetent in that other skill despite both being essentially specialties of the same core function. Which is NOT how skills work in reality. People who know how to fight with swords do not suddenly forget how to fight because they pick up an axe.
This sort of system is overly punishing and inefficient, and does not reflect reality. This isn't even a dig against long skill lists (in the sense of defining specific functions), specifically, but about implementation. Specific functions ideally should still exist, but they should NOT be treated as separate unrelated skills, but as specialties of general skills dealing with core, universal functions, like melee combat, ranged combat, technology, academic knowledge or piloting. That way you have general competency in one core function, but may still define things you've specifically mastered within those areas of activity, rather than spread Every. Single. Point. you've got into a dozen variations of the same thing, that might not even come up during play, just to have mild competency in those areas.
I respectfully disagree for two reasons. 1) Swords and axes are used very differently; they have different striking motions, muscle groups, and tactics. Granted this is a quibble over one example, and I agree that in real life being skilled in combat in general affects different weapon skills. 2) That said, in a game your solution would get lost in the mushiness of rolling dice. Say my sword skill is 60% and my axe skill is 10%. Your argument seems to be that some sword skill overflows into axe, so axe should really be what 30%? Thing is, I'm mostly going to use sword anyway and the few times I use axe, the difference between 10% and 30% is not going to register as statistically significant. If I use axe to the extent that 30% vs 10% does become statistically significant, then axe should still artificially suck for sake of narrative. If multiple weapons skills are all close in level and training in one means training in another, then what's the point in specializing? Without forcing specialization, choices become gray and characters become samey. I might as well throw points into bladed weapons because it benefits sword and axe. Soon all characters are all pretty good at both. IMO, it's better to have the sword guy and the axe guy, even if a little unrealistic.
1) Striking motions for most melee weapons are almost identical and share practically the same muscle groups. I know cuz weapon training is my go-to physical exercise these days, and I train primarily with swords and staves, but have also messed around with knives, hammers, walking canes and sticks, and they all tend to translate (stick fighting in particular is identical with swords, and canes have much in common with sticks--and therefore swords--and staves). Even seemingly disparate weapons like swords vs poles involve similar maneuvers that work basically the same muscles. You just need to compensate for different weight distribution and dimensions, and occasionally for special features, like hooks (if you're fighting with a walking cane or using the axe head as a hooking implement). But such features don't require drastically different techniques than what you'd normally use when striking or tripping opponents, and once you become experienced with fighting techniques, it becomes almost second nature to figure out how to use those features (hooking with a cane is very similar to tripping with a stave, only easier, cuz the hook gives you an edge).
Edit: Even when you need specific training to properly handle a weapon, that training is more in terms of "becoming used to the weapon", than learning radically different techniques. And once you master a weapon you pretty much can fight at the same level as you would with any other weapon. In old D&D or 3e terms, is more like gaining "proficiency", rather than leaning an entirely new skill.
2) What I'm proposing is making general skills the ONLY "skills" in terms of level development and specializations basically a one time bonus (like maybe +2 or so, depending on the system) on top of your skill level. Depending on how granular you want it to be, specialties could gain multiple ranks for increased bonuses, but I wouldn't recommend making it more than two or three ranks tops (Expert, Master, Grandmaster?). Also, the idea that you would only use a sword is very meta. Sometimes all you have is a stick you found in the ground. Granted, in game play that relies on the GM paying attention to stuff like disarming, or potentially losing your weapon if you fall, etc.