notahuman The government could have demanded google create a backdoor in the hardware and issued a gag order.
In theory, yes... but...
In theory there is no difference between theory and practice, while in practice there is.
--Benjamin Brewster, Yale Literary Magazine, February 1882
The U.S. government could mandate that Google include mass-surveillance backdoors in all of their phones, and could maybe include a gag order. But that sort of argument could cover anything. Way back in 1949 George Orwell wrote a book in which every television was a government surveillance device, which is trivial now (in fact, smart-TV companies have been found doing surveillance for profit). And these days every car could be a surveillance device, and every Wi-Fi access point, and, heck, every automatic paper-towel dispenser in every restroom.
The problem with sweeping mass-surveillance conspiracies is that when they're big enough they are disclosed. Google ships new phones every year, so does Samsung, so does Apple... keeping something like that a secret, across all of those design teams, year after year, would be a monumental effort.
People are aware of the Crypto AG compromise, but that worked as well as it did because it was one small company. Even before Snowden made his disclosures, people suspected some of those holes. There are multiple mass-surveillance/public-safety infrastructures in China, but they are so big that everybody knows about them.
If the NSA, or the FBI, whatever, wants to bug me in particular, and they are willing to spend $50,000 or so, I have to assume they'll be successful. "Retail" (targeted, individual) surveillance generally works. "Wholesale" surveillance can work too, but secret "wholesale" surveillance is a lot harder.
I don't think it's "naive" to assume that secret wholesale surveillance would be disclosed. Gag orders can work when they are limited in scope, but I think data support the notion that grand sweeping multi-year multi-company gag orders eventually leak.