At this point it is all up to Nintendo to carry the console market in Japan unless Sony decides to make another handheld. If the next console does PS3 or PS4 numbers then we are in trouble.
nintendo basically checked sony by making the switch.
a dedicated handheld would either be too weak compared to the switch, or to expensive to justify being 'only' a handheld (last gen showed this, 250 is too expesive for a dedicated handheld to the point nintendo did an unprecidented year 1 MASSIVE price drop).
If they follow nintendo on the hybrid concept, thats leaving the power hungry western devs and users soly to microsoft.