I'm excited to play the game but admittedly my enthusiasm has been dulled a bit since the reviews came out. The ones I read never really mentioned the plot.

Sadly, I don't know the exact review restrictions, but it isn't uncommon for companies to dictate what you can/can't say in a review. Before people rush in to talk about shadow organizations and back room deals, it's almost always done in a logical way.

For instance, most visual novels have restrictions after a certain point. So I can't say XYZ is the killer or ABC is going to happen, but this is just to make sure nothing is ruined. Tearaway had one on the ending, since they didn't want reviewers to take away from the joy there. In the case of Breath of the Wild, we've seen Nintendo be VERY cautious on showing/talking about anything related to the story and it seems to be because they don't want it to be ruined.

There is one and all the positive reviews strongly indicate, by score alone, it's good, even if reviews rarely mention it.

SN Also, if this is not the reason, it could just be choice. Like a lot of reviews, such as IGNs, for Mario Party 10 didn't mention the lack of online.