Yes, it's really not that hard to understand.
Using one word with an obvious denotation and then claiming that you are actually referring to some obscure connotation is not exactly a good way to communicate. If you say "shitty," people will likely assume you mean "crappy, bad, poor, worthless" and that was certainly qualified by the rest of your statement. If you meant something else (and what else could you mean, honestly), then you might want to choose different words that don't lead people to misunderstand you.
Wow, what a stunningly cynical interpretation of the FPS genre. You're suggesting that
A| Nintendo couldn't make an FPS which is genuinely innovative (and you're a fan, apparently)
B| All FPS games are inherently bad
Also, the Wii U isn't exactly a typical representation of the gaming landscape. The number of 2D platformers on Nintendo's systems overwhelms the number of shooters, and considering how popular that genre is, don't you deem it sensible for Nintendo to sacrifice [one 2D platformer in favour of something different?
Ironically, it seems like you totally misinterpreted that poster's point. S/he is merely saying that the market is currently saturated (or in some people's views, oversaturated) with first-person shooters, and thus it's questionable as to what Nintendo stands to gain by trying to devote a huge project to capturing that market, regardless of how they might innovate in the genre. And there was nothing said about all FPS games being bad, only that there's a lot of them - obviously some good, some bad.
You're also assuming that just because the FPS genre is popular, that people would naturally flock to an FPS made by Nintendo or on a Nintendo platform, or that that game would automatically perform better than one of their platformers. There's a lot of market and cultural factors that render such an assumption questionable, if not erroneous. It might be interesting for Nintendo pursue such a project, and maybe one of their teams will, but it's really unknown how much they stand to gain from entering such a highly competitive space, especially compared to platformers, which they understand very well.
In short, I don't think most people are antagonistic to Nintendo making a FPS (not attached to the Metroid brand, anyway, because obviously that only has so much appeal to the FPS crowd). But the sentiment your average Call of Duty player maintains toward Nintendo as a company and as a brand would make apparent the difficulties of them reaching that market. And given how many other companies are producing such games, Nintendo's logic is pretty clear: why potentially waste millions of dollars experimenting in a genre we have minimal experience in and that many other developers already succeed in, when there's no clear indication that the majority of consumers want such a game from us?
