PHATsakk43
Last Authlim of the True Lord of Tyranny
What you’re describing—5E method which is mostly an afterthought of or consequence of a combination of class, species, and background, with a modicum of design in the way of ability score selection seems like it’s simply mechanical.That seems to be a highly idiosyncratic definition of a "skill system", and not one very useful foe actual analysis.
A better definition of a "skill system", IMO, ia a system thet helps differentiate the results of an action declaration from two characters using two or more factors. So, "roll under attribute" is not a "skill system" because the results are only differentiated in one dimension, Attribute score. Whereas in 5Ez the combination of Attribute, Proficiency, Expertise and certain Class abilities provide nuance and multiple shades of distinction between different characters declaring the same action.
Sure, the method in either AD&D or 3E/3.5/PF is absolutely idiosyncratic—which is the reason for a defined system. Otherwise it’s simply another ability that is simply baked into the character creation process.
Skills systems are by their natures idiosyncratic. Or ought to be.
Again, I use the system provided in 5E—RAW—because it’s not idiosyncratic which simplifies things. Sometimes simplicity is just what is needed or wanted.
When I want a more developed game, but without the problems I think exist in the other D20 games—precisely because those don’t use a bounded accuracy basis—I run a well optioned 2E game.