It doesn't help that the aircraft are trash too, people do notice these things! I had some friends recently fly outbound on the A330 to PHL and back via JFK on the 767, they said they couldn't believe the 767 still had overhead TVs...!
They may be in the process of tarting up the 767 business cabins (still the risk of angle flats yet) but the economy cabins will remain dated. And nobody is getting seat back entertainment either, people expect that these days. Oh and you never know if they will switch the route to a 757 either.
I've got a couple of J TATLs on AA coming up and I am going via LHR for the better and more predictable experience. I can't be the only one who values that!