I agree with you. The way our language has evolved, "retard" no longer refers to people who are challenged in their intellectual skills. It refers to people who say or do something that they didn't completely think out and wish they had.
This whole thing with unacceptable words just stops language from evolving and burdens our thought processes. We're concentrating too much on what are acceptable words and not getting to the person or message behind them. She didn't slander anyone; Aniston just spoke in an honest way.
I'll be in the minority here. I like Jennifer Aniston as an actress. She brings something positive to every role. And this one....I thought it was more of a satire about relationships today.
Oh my goodness, we wouldn't want to burden anyone's thought processes. We all need to do more thought processing, starting right now.
And, I don't think language could possible evolve any lower.