Well an actual abrasion is where you scrape the surface of the skin... so it is definitely a bit more than an "owie".
Serious abrasions are literally when you rip the topmost layer of your skin off so it being the type of debuff in game I feel like is appropriate.
Road rash is a super serious abrasion that motorcyclists can get when they wipe out (imagine if with the wobbly mechanics the motorcycle has if we had
a way to wipe out and fall off and have an 8-hour in-game roadrash debuff).
It is annoying, can be treated easily, but it will potentially cause pain and/or discomfort (in game mechanics, the debuff) until it goes away.
I feel like for how it is represented in game it is fairly accurate.
Edit: Although in thinking about it, it would be nice if it gave a very small movement penalty since sometimes if you get a really good scrape IRL you aren't fully moving if the abrasion is in the right spot. Or as someone else said, an untreated one could randomly lead to infection which can happen.