Personally, I think the game'll be pretty great when it comes out. No Man's Sky built up hype by showing very small, scripted sections and interviews where the designer rattled off features that never made it into the game. In contrast, we've seen a combined ~4 hours of BotW gameplay executed very naturally by a group of testers.
oops, i forgot to respond to this.
yep, showing so much uninterrupted footage is definitely a sign of confidence and i think the game looks great.
that said, imo the main concern is how long it takes for the game to get stale. this almost always an issue with open world games because they rely so much on a compelling core gameplay loop. we've seen 4 hours of activities that mostly look very fun, but will they still be fun after 50 hours is what i'm trying to say.