It is hard to understand Japanese mindset with gaming. Superb games like "Judge Eyes" deserve better. I would never know PS4 numbers in Japan are low if were not for this site. The console is so huge here where I live. I feel here in the West SEGA will promote "Judge Eyes" really well so I think it will do great.
portability is really important in Japan. I lived there for one year and I could see people playing to 3ds in train often (I had higher expectations tho). Also, in my opinion, its a society where trends are really important, for example, if smash is a hit, everybody is gonna buy it and talk about it with their friends. So even if ps4 offers a wide variety of famous games in japan (kh, final fantasy, monster hunter, dragon quest...) people will buy the switch and its games since most of the exclusives are too big in the country (pokemon, animal crossing, smash, splatoon, mario, zelda...).
Also I think graphics are not that important as in EU or USA since many people play many smartphone games on trains, bus...