AA exec plat requires 100k EQM, and 12K USD spending. assuming you dont fly AA, you earn 1.5 EQM per miles flown in J class. so. you need to fly 67K to qualify.

BA requires 1500 tier points. each J class over 2000 miles earn 140 tier points.
it takes 11 flights in business class in J class to earn BA gold (oneworld emerald equivalent.) as little as 22000 miles flown in business class.

For people who fly mostly business class, and not very often, BA is the best program. If you do fly a lot of miles like long haul LHR-SYD/USA often, the calculation is very difficult.