3DS was far from blue ocean it wasn't even close this starts off with the pricing debacle just because they use the same branding doesn't mean the approach is the same it's this mode of thinking that caused Nintendo problems, people bought the DS because not only was it a accessible, new and appealing concept it was vastly affordable those are the main things the blue ocean work on 3DS just used the same branding and went down a different road thinking that if they threw out a token release it would yield the same result but they soon found out token releases aren't really catering to an audience. This is why the 3DS ran into trouble early on (also why Wii U flopped) and why they abandoned their plan and shifted the way they handled it and dropped 3DS entirely from the marketing by the time Vita arrived 3DS was already saved it had its price cut and focus had shifted to its software one of the biggest weeks for 3DS came during Vita's launched as that was the week Monster Hunter released on 3DS.
WiiU is more powerful than PS3/360 that's not even debatable as running one of the same games of the gen at 1080p highlights this it's an objective those were the consoles out at the time for the good part of the year until the rest of Gen 8 launched this is relevant because Wii rather than outmatch prior gen stuck with in the same level of its predecessor to push a concept graphics was never its goal where as Wii U's HD performance was parroted by Nintendo when the platform was announced it was a complete shift. You link Miyamoto here's Reggie's own words when the platform was unveiled.
"It's a system we will all enjoy together but also one that's tailor-made for you"
This was also a reason given as to why Wii U wasn't called Wii 2 or Wii HD as the concepts and goals were different Wii U was a successor not a continuation so no my point still stands, what actually went wrong with the platform was Nintendo not knowing what they wanted the platform to be, who they were aiming for and not doing their own thing like they normally do. People ended up not caring because they weren't given reason to care the casuals weren't being catered to, the cores already had their choice of platforms set, Nintendo fell into the trap of chasing the crowd of other platforms by trying to mimic other platforms which reduced the value of getting it as why get an imitation when you can get the original.
With the Switch they did what they wanted to do, knew what they wanted the platform to be, who they were aiming for and as such were able to handle the platform far better.