This is easy to say when you live in a situation where you're part of the majority and all your behavior is within strict limits of the current culture.
Take homosexuality for example. Having that information in the open means death in plenty of places. In addition, even in places like the USA it has become accepted only fairly recently but would have gotten you in serious trouble a while back. Culture change can't happen if any event towards this change is immediately punished. The change needs to start small in closed private social circles. Only when a lot of private battles have been won is there hope for a more mainstream acceptance of a new norm.
Take being Jewish for example. In 1920s Germany it wasn't that big of a deal if people knew you were Jewish. However things changed, different people got in power and started to abuse it. What was previously a simple case of "I got nothing to hide" suddenly turned into a question of life & death. It's naive to think that these kind of events will never happen again in any place in the world.
Losing privacy would greatly hurt any cultural change that needs private law breaking, and this includes any future laws.
As for technological progress stopping, of course it isn't going to stop. However this goes both ways. Privacy protecting technology also has progress. Any technology that reduces privacy has a counter-technology that protects privacy. What's more, we can use the same political system that could hurt us with a lack of privacy to instead protect our privacy by prohibiting/limiting privacy breaking activities.
Of course no progress just inherently happens. There are actual driven & talented people working on both sides every day. There is no inevitable victor here, there isn't even a clearly leading side yet, it's very close with strong trends in both privacy-reducing & privacy-increasing directions. Every contribution matters and it's definitely not too late to decisively lead us to a far more private world.