We call it "shipping the org chart." Your fundamental error is assuming that there is any one person -- or even center of authority -- in charge of brand communication.
I get that there are a lot of different groups at Google and they all have their own vision of their own part of the universe, and its super empowering to tell every product manager "Hey, if you can get it market ready you can ship it!" The part that I don't get is that people working for Google aren't clueless. I know a lot of smart people that work there still. So why tolerate a company behavior that is so harmful to their consumer image? Rebranding is treated like a dot dot release it seems. Sure you can get away from a stigma maybe for a bad choice but rebranding on a whim? This stuff has to go through legal right? Trademarks and all that. Who decided to make Pixel a phone? And to just sort of drop the whole Nexus thing? (here is a funny discussion about the Pixel trademark: http://thetrademarkninja.com/2016/10/03/google-event-tradema...)
What it means is that nobody in any authority at Google understands brands, and that is a big red flag for Google's aspirations in the product space.
Because they make more money than God? I mean, okay, some customer somewhere is mad at Google abstractly, but not mad enough to stop paying Google (still use Android/gmail/g-suite/buy chromebooks/use chrome). If a tree falls in the woods and nobody hears it, does it make a sound?
edit: For real, they "tolerate" it because looking ahead into a future where this "harm" to their "customer image" does actual harm to Google is really hard. Maybe it happens, maybe it doesn't, but no one can say how likely or precisely when. So, make hay while the sun shines?
PS: perhaps Apple was able to achieve "centralized creativity" only because of Jobs.
Metaphoric org charts of tech companies: http://ritholtz.com/wp-content/uploads/2013/07/2011.06.27_or...
Compare to for example Apple which seems to think so much they get very little out.
Maybe it is very difficult for large organisation to find the balance between these two. Grand vision requires somebody to manage it and filter what gets out. That can lead to great products getting killed just because they were not invented by the VP Visions.