Your not listening. Mobile devices including mobile consoles took over Japanese gaming. Home consoles were dying.. Wii U bombed compared to Wii, XB1 bombed compared 360. After 1 year of sales people said ps4 was going to bomb too compared to ps3.
But it bucked the market trend and is up on ps3. Given the circumstances it's a miracle. Shows what a beast the ps4 is that it could buck the trend.
Even 3DS was down on it's predecessor. Even Switch. Even vita. Ps4 is the only one standing.