I agree with you but I think it is better that people realise this and then use the device as ‘as free as we can get without making me a hermit’ instead of just hiding it.
The point is - it is truly 100% free at the level that actually matters: the user controlled operating system. This is the point where I feel completely comfortable with calling it "100% free" without further explanation (especially when the last, and I think the only, smartphone to ever reach that level was GTA02 from 2008), just as I am completely comfortable with saying "I made this cake from scratch" without having invented a universe.