Booked AA metal at saver rate that AA would not release to its own members. This includes TATL and domestic segments - that AA shows exuberant pricing like in 100 to 200K one way on AA's own metal TATL. Domestic U also at outrageous pricing. Yet AS can see the partner saver seats. Plus AS still allows a free stopover on Int'l one way.
Change on itinerary is very easily done on AS website. 70% of the time you can do it yourself without having to call. That is far superior than AA.

My take is, it has been like that but much much more so, that one cannot have a pre-set destination(s) in mind and then try to find availability towards that destination(s). One has to be truly truly flexible not just the dates but also the places you go. For example, you can go anywhere in Europe then make your way to where you particularly want / need to go. That would make finding availability much easier.
Sometimes it makes more sense to either take a 4 to 5 hours train or an LCC flight to make the itinerary work, while actually the tax saving might be more than enough to pay for the position train / LCC flights. Been like this in the past but much more so these days.