I have reached this conclusion with regret, and only after semi-extensive product testing. It's not that I don't like Japanese food overall; I enjoy miso soup and rice and fish and all the rest, and I'm not talking about that those confusing, fifty-ingredient culinary masterpieces they whip up on Iron Chef. What I don't like about Japanese dishes is the presentation style.
I don't dislike the ingredients, for the most part. What I don't like is how they serve them to you, usually in huge chunks. You'll get a cauldron of broth with meat and vegetables, and floating in the soup will be a huge shrimp, with legs and antenna and everything. And like half a carrot, and a whole head of bok choi, and half a fillet of cod, and two full leaves of Chinese mustard, etc. This presentation style is necessitated by the handicap of having to make things edible with chopsticks, and over time the Japanese eater has come to expect huge bites of a single ingredient. It's only logical; you can easily snatch up a finger-length piece of carrot and chomp it down in one bite, while you would get very bored chopstick fishing for two dozen slices of carrot in the same bowl. The same goes for huge hunks of chicken or fish or beef or various other vegetables. I'm not knocking their presentation or preparation style; I'm sure many people enjoy it.
Unfortunately, I am not one of them. I like to taste a bit of all the ingredients in every bite. I make sandwiches with lots of thinly-sliced meats and cheeses and vegetables, I like soup with tons of things cut small enough to fit easily into my spoon, I regularly prepare stir fry with upwards of a dozen components, etc. So in theory, I could take any Japanese dish with ingredients I liked, chop it up into 1/8th sized pieces, and be pretty happy. Perhaps I'll try that next time, rather than taking nibbles of numerous things in rapid succession, and dropping each of them back into the bowl for later consumption. Of course I'd need a knife and a fork and a cutting surface, rather than just two blunt pieces of wood, but no one said it would be easy.
Update: I do like tempura, but that hardly counts; as we all know, anything is good battered and deep fried. As for sushi, I like a few types, usually involving shrimp and rice, but sushi is grossly overpriced everywhere other than at a buffet like Todai, and there's no rice or fish dish I like better cold than hot. So I can basically tolerate sushi for free, but would never go out of my way to order it. (Which is a shame, since Malaya likes lots of sushi and absolutely loves saba.)
Honestly, in the case of tempura and sushi, I just order them to have an excuse to eat wasabi. I love that stuff, especially mixed up in a dipping dish with some soy sauce, though I quite enjoy it alone. A healthy dab of that stuff all by itself makes me very happy, especially if I do it the freebase style and take a bite, use my tongue to rub it into the top of my mouth, then smile while tears run down my face and my sinuses explode.