For me, the six attributes were also about flavor. They were your way of telling yourself that your character was this strong, this smart and could move like a dead snail. I couldn't care less if it's not challenging to pick your stats because that's not what it was about.
In PoE, it feels like too much like a mechanical exercise, carefully constructed so you really don't know what to pick, and sadly also so you might as well go with the same distrubtion for different classes. I actually enjoyed the fact that in AD&D, different classes need different attributes. If you're a skinny bookworm who faints at the sight of blood, you really are more likely to become a mage than a fighter. Somewhere along the way, some people apparently started to hate these fantasy stereotypes.
The system is by no means going to be a deal-breaker for me, and I can't really say I expect it to change all that much, but I can't help but ask the following question: if we really want every attribute to matter equally much to everyone, why don't we simply throw out all the attributes? I know it has been said already, but I'm seriously wondering if we couldn't just as well do that.