I don't see anything wrong with that personally. People are voicing their opinions on stuff and that's fine whether or not I agree with them.
It's not really about the opinions so much as how they word them.
"I'm a bit worried about how this is going to turn out considering the concept, but we'll see how it works" is a bit different from "This machine isn't exactly like what I wanted? That's it, forget that we haven't even seen this thing yet, I'm not buying it! Burn in Hell Nintendo, see you when you're third party!" or "Wow the more I hear about this the more disappointed I get. Why do you keep failing me Nintendo?"
We haven't even seen what the system looks like, let alone the system in action, and people are already boycotting it. An opinion is one thing, but I feel like people are getting a bit. . .reactionary.
I feel like there has to be a way for people to voice concerns without acting like a mob of wet blankets. :/