Yes but that's very obvious, the route just discussed is subtle and difficult to detect.
And besides, if I were a state actor and I wanted to sink a program like Signal through such subversive means, I'd probably have someone start contributing to the project, and then start arguing in favor of bad UX choices; make it harder to use, not just unreliable, in favor of "security". Push it out of the realm of what a normal user could conceivably make use of.
That's the kind of long con I'd play -- play on techies' love of doing things on principle and for theoretical purposes, and general disinterest in UX.