>>714181848They really aren't, no.
Sony, since the PS2, has been making pre-built PCs essentially. They were more transparent about that when they let you put your own OS on the consoles, but that has always been what they were doing since the PS2.
Xbox exists specifically for that reason.
Nintendo stopped competing with this. That's what happened. You cannot genuinely look at how Nintendo handled itself from the NES to the GCN and go "Yeah, what they're doing with the Wii, Wii U, and Switch is exactly the same".
They no longer aim for cutting edge hardware. They no longer desire having all "current" third parties on their platforms. Their primary focus has shifted from a console environment to a brand environment, where the primary reason in purchasing a Nintendo console is for the Nintendo ecosystem of titles, with third parties being a bonus.
>>714181834Actually, it was more likely due to the abject failure of Yakuza 1&2 on Wii U.