Very much. I also fear they coming for this, we already have instances of where using secure alternatives tags you as a criminal[0], so i don't doubt a future where non-approved applications will get you in trouble. With everything happening around Android locking itself down[1] and Windows being a spyware[2] anybody who wants privacy will be 'different', and can be tagged and excluded from parts of society for not using the same services.
[0]: https://x.com/GrapheneOS/status/1940440326830989549
Imagine all I ever posted was cat pics... unless I have your public key and then all of a sudden those pics are decoded into messages of dissent
Google is already working on closing the possibility to install apps from outside the app store, Apple has been like that since forever. The fact that a few technically savvy users with rooted phones will still be able to use Signal doesn't mean anything. It will be dead if the EU decides they don't want it.
https://en.wikipedia.org/wiki/National_security_letter
the government can compel entities to let them access their systems and keep it a secret.
Also, if Signal runs on AWS, that is another potential vector of surveillance.