It is not a question of can/should.
It is a question of should/must.
AA should refund the money just on business savvy part.
From the wording of AA's own website, AA MUST refund the money. (a change of seat has occured)
For people keep saying the same category of seat was given to OP.
Will you accept, before the wedding, your bridal gown store tells you. "sorry the dress you want is not available, you can have this equal value one"
How about "sorry the house you pick with a open view is given to a disable person, how about this equal value house 5 doors down that face a brick wall"