traditionally animated films struggle to earn money in general, nowadays, let alone japanese ones. just look at The Princess and the Frog. that movie did well, but you can bet your ass that it would have probably made twice as much if it were digitally animated.
add a foreign element to the traditional animation and you are just not very likely to see big box office numbers. distributors just arent willing to take a chance on any foreign animated film that isnt Studio Ghibli, and only because their movies are profitable, usually. and even then, the top three highest grossing anime films (all Ghibli) are only moderately successful compared to the biggest american animated films of EACH YEAR.
ever since like 2006, just the two top-grossing american animated films combined have earned over a billion dollars, and as we have seen with Toy Story 3 and Frozen, it is possible to break a billion with just one. you would have to add the top five highest grossing anime films of ALL TIME before you added up to a billion dollars.
its just all about the money. with the exception of the first two Pokemon movies, Studio Ghibli is the only japanese animation studio to produce films that break 100 million dollars, but only six times. of those six, only half managed to earn 200 million.
compare that to Disney Animation Studios, who have only delivered one movie in nearly fifteen years to not break 100 million dollars (Winnie the Pooh, traditionally animated)
or to Sony Animation Studios, who, ever since starting as late as 2006, have never delivered a film that didnt break 100 million.
or to Dreamworks Animation, who in the past decade have put out movies that either break or come close to breaking 200 million.
or to Blue Sky Studios, whose films have never failed to earn less than 250 million
or best of all, compare that to Pixar, whose films have never made less than 350 million. Spirited Away, the highest-grossing anime film of all time still earned nearly 100 million less than Pixar's lowest-grossing film.
and it isnt just traditionally animated films that struggle. stop motion animation also doesnt earn much at the box office, with numbers even lower than that of the top anime films.
honestly, as much as i like anime and traditionally animated films in general, if i were a studio executive, i would argue against producing or distributing any traditionally animated movie that isnt based on a very popular cartoon or isnt made my Studio Ghibli. theres just too much risk and too little profit... but if i were head of an animation studio, i would still make them, because someone has to, this day in age. traditional big screen animation is practically dead.