I see the OP referred to taxes and fees. I don't expect "fees" to be refunded but what about taxes?
An UA thread
Taxes on non-refundable tickets
AA site says
You may be entitled to a refund of some taxes included in the price of your ticket:

Upon written request, taxes or fees not imposed by the airline that are specific to destinations can be refunded
Taxes or fees won't be refunded if American has an obligation to pay regardless of travel
Refundable taxes and fees will be refunded to the original form of payment



what about this:
http://www.re-fund.com/how-to-get-an...unused-ticket/

which of the ffollowing taxes and fees does AA have an obligation to pay irrespective of actual travel:

Adult (per passenger) $87.44 USD
PASSENGER FACILITY CHARGE (UNITED STATES) $4.50 USD
SEGMENT TAX (UNITED STATES) $4.20 USD
TRANSPORTATION TAX (UNITED STATES) $6.56 USD
US SECURITY FEE (UNITED STATES) $5.60 USD
Total $108.30 USD per person

Now you have to apply in writing ??
which of the above taxes would "American have an obligation to pay irrespective of travel.

Also Why does there "obligation" disappear when it a full fare, fully unrestricted ticket?? afterall That consumer gets a full refund

This is my issue , this is a very speculative booking. I don't know if my pair of tixs will be used. I'm a big boy and am happy to throw away the base fare , but the $44 for two tixs is actually a factor.
Snice 20% likelihood of travel. But at $87 base fare, I'm willing to take a 80% chance of throwing away the tixs.
In the past taxes went back automatically.
What TAXES on this garden variety domestic only Its garden varity pedestrian is AA "obligated" to remit ( the term should be "remit ", not pay) .
Snice AA is making it a lot more cumbersome to get a refund of taxes what happens to the taxes collected on non refundable cancelled tickets prior to departure?