It is hard to read this any other way then - you are in a privileged position of having never been personally challenged by a lack of privacy so are fine with privacy not existing. By that reasoning you are also OK with those who are effected being silenced, because they are, for example, not cisgender, white skinned and male and could face attack for random individuals for expressing their views in public.

The challenging thing about reading books like Bonhoffer is that it compels you to questioning what your response would have been if placed in the same situation.

We won't be able to prevent it only if we accept it. The erosion of privacy is self-imposed, so if it brings damage and people consider it important, it will stop.

Our world is non-ideal in many ways, and there are many potential sacrifices one could make to help improve our future. Using more private technology is one of them, but so are things like avoiding flying, going vegan, switching careers to directly work on a problem, or donating to support progress in these or other areas. I think it's pretty hard to make a case that trying to hold back the large decrease in privacy is more altruistically valuable than, say, trying to keep humanity from wiping itself out (nukes, bioengineering, AI, etc).

Interesting, but those aren't very high stakes controversial opinions. People may strongly disagree with them, but they aren't likely to lead to a declined job offer, workplace difficulties or harassment. There are many stances for which making a public case is futile because people have strong emotional commitments around them. Would you still be public about them?

Yes, I would still be public. I think making a case is almost never futile: I don't think I've ever encountered a topic where there weren't some people (often the quieter ones) who cared about the arguments.