I read Snowden's biography - Permanent Record. Your claims are untrue. The sibling comment has it right - the US govt could steal data from the tech giants but they gradually got better at plugging such leaks. For example, in response to the Snowden revelations, all data in transit between datacenters is now encrypted. On the other hand, the govt would also request the data of a few people, which was generally granted.
It's not correct that the US govt has root access to all systems and data.
That seems extraordinarily naive. The NSA would not give up access like that unless forced at gunpoint, and the US gov has clearly demonstrated it doesn't care (and actually quite likes) this sort of gross privacy invasion.
The only (in)tangible difference between 2005 and today is the presumed existence of national security letters and other warrants that compel these companies to provide access.
You must be ignorant of how these agencies work. All they want is plausible deniability. The spy agencies have all technology needed to access any phone. For example, it is widely known that Israel's agencies have the ability to enter any phone, iOS or Android, and get the information they want. They are now OPENLY using this technology to track corona virus cases:
It's not correct that the US govt has root access to all systems and data.