I'm wondering why there's an NDA too. This is a game I paid $80 for years ago.
I'll be blunt. This is not the game you paid $80. That game ended in November. The videos are clear indications that this game is something different.
As far as giving people who are courious an uneasy feeling. That entirely depends on the level of courious they are. Those who are strapped to their seat, like you and I, waiting for every scrap of info to leak out publicly to chat over, will always feel like there's room for more opinions and more feedback.
But I imagine there's only so much server space and if they made all aspects of the Beta Public, the demands to get in the beta would be pretty darn high. They limit their sample source so they can listen more closely, I suppose.
Also, we need to remember this is the internet. There is no stable middle ground to form an opinion off of. Everyone's opinions must fall in line with one stereotype or the other, equally extreme and opposing stereotype, which you are playing as a perfect example of.
I don't think this game will fail. Likewise I don't expect this game to be the best that's ever come out, or to fit everyone's tastes. I do expect it to survive nicely like FFXI did, finding its niche and sticking to it. This is an easy conjecture to make due to how previous FF titles have always been - having a core fan base with others debating what they like and hated about it. If SE can achieve even that, then they accomplished what they set out to do - which is reach the quality expected of the Final Fantasy franchise. Personally, that's all I ask of them as well.