Bill Zebub
“It’s probably Matt Mercer’s fault.”
But if ability scores do not differentiate characters, why are we having them? Why we have elaborate systems for buying and boosting numbers that do not mean anything?
I have to agree with you there. To be a little hyperbolic, we really just need 2: Constitution, and "Your Primary Attribute", which you could fluff however you want.
More soberly, different attributes affect skills and saving throws and maybe a few other things. But in combat (which is by far the most mechanically significant part of the game) Dex helps (sometimes) with AC and Initiative, and otherwise all that matters is Con and Primary. That bugs me about 5e.
However, while I agree with you here, "differentiating characters with attributes" and "differentiating races with attributes" are, in my mind, two entirely different topics. If we assume that 5e does a poor job differentiating characters with attributes in general, it follows that they do a poor job differentiating races as well.