Having read comments here before watching last night, I had some sense for what it could be like beforehand.
I liked the guest segments that highlighted what the products can do. The photographer one was probably the most "real", and I thought Steph Curry did a nice job in his skit.
That said I can understand the reactions and perceptions. Being used to more the more capabilities and features oriented Google I/O, Apple and Samsung events, this Made by Google event was not in that vein, rather as noted by many in the comments above, more for those who may not focus on the technical details.