Why should Ubuntu have a backdoor and Gentoo, for example, not? Ubuntu's code is much more audited. If we get paranoid, the real problem is the hardware. Most hardware manufacturers are beholden to the NSA and the Chinese government, and there is a lot of documentation about backdoors in the hardware exploited by the NSA. There is a misconception about Linux distributions here. Why are Ubuntu or Red Hat bad? Because they make money? Would Linux be sustainable if it didn't make money? Free software doesn't mean you can't make money. Red Hat is the distribution that brings the most innovations to Linux, for example. Sytemd is another matter, but that's another book.