Yeah you make a really good point (especially with those two examples, which the latter might not even require data collection at all). But I do think that an arms race in this direction would change the public view. You'd sure have a lot fewer nerds like us arguing about privacy. Though we'd probably be arguing more for open source to lessen the trust issue.

I don't think we'll ever have fully trust-less systems. But I do think there's a big difference between saying "trust us, we don't look at the data" vs "we encrypted the data and use this method, trust us that we aren't decrypting it". The former method is worse because there's a lot of people that have clear access to the data. The latter is better because there are more speed bumps and the argument is more sound. A lot of trust is built from demonstrating good faith efforts.