Is there a meaningful distinction? Yes there is, whatever you want to call it there is definitely a meaningful difference between describing the basic attributes and filling in the attributes for a character. Which leads into the first of the two... not quite counter points but things to keep in mind.

First it isn't a hard divide. You have a scale based on systems, but a similar scale exists for content. Core rules are on one end, then we can pass through sub-system rules, guidelines and defaults and then individual pieces of content. And I'm not sure how character creation and character abilities fit into this so some would be hard to pin down, but there are different levels of "is pinned down throughout the system" rules can have.

Second is I don't think discussing one in isolation is going to be very useful. For a simple example, talking about D20 variance in practice is actually really hard to do without knowing other things in the system, like the range of modifiers in the system, and although systems will tend towards different types of values they do depend on individual types of content.