In regards to the Vita I think it is more the case that the Sony fans, and to a large extent even the most vocal fans for the platform. Have copped to the reality or it all, and arguments for good future prospects seem to be halfhearted, or downright lethargic. It is fast becoming a absolute truth that the Vita is destined for failure. It isn't quite there yet, but for the most part the absolute denial is gone.
Meanwhile there is more sport to be had with Nintendo fans, because most of them got caught flat footed, and never really considered the possibility that the new console could actually sell this poorly, or that Nintendo could even have a failure. Which is kind of perplexing, because Nintendo has as much failed hardware as they have had hardware that did well. This is the company after all that gave us the Virtual Boy, The 64DD, The Super Scope, The Power Glove, and R.O.B the Robot.
Nintendo actually has a surprisingly high failure rate. So it should have been at least a possibility in their minds. In reality it was probably a anomaly that the Wii did as well as it did. The right quirky device at just the right time, but most of the time Nintendo fails to hit the mark with its quirky initiatives. The Wii U design was, and is quirky so it really should be considered against that group as a whole. Rather then against consoles like the N64, GameCube, and the NES branded consoles. Those were safer design choices. Where as those other devices weren't all that safe from the get go.
Taking big risks isn't just synonymous with high rewards. It is also synonymous with high failure rates. I am not saying that the latter is the Wii U, but the fact that it could be a dud. Should have been higher in the minds of some fans. If I were a Nintendo fan I would hold my breath when it came to launches. I used to game with Nintendo, and got burned many a time by things they sold me only to abandon in just a few months.
I suppose there is also a dark upside to all of this. Nintendo doesn't really have any qualms about abandoning hardware. If the Wii U doesn't catch on. Nintendo isn't like the other two. They will dump the hardware, and cook up a replacement. So the brand isn't inexorably linked to this specific hardware. Obviously not ideal for anyone who bought the Wii U, but if you have been a Nintendo fan longer then the past generation. You have probably grown to accept that this company has a habit of the old dump and run. Hell sometimes it starts running before it even dumps.
I am not trying to be a ass about it, but I see a lot of Nintendo fans that just don't seem to get Nintendo. Which sadly a lot of fans of other brands are none to shy of reminding them about. The company got a lot of bad rep for a reason in the first place. Nintendo has a real arsonists touch, and fans have gotten burned by them plenty of times. Any truly old school fan of Nintendo knows to keep expectations in check.