1. No, services in the US like DDG largely aren't liable for what users post (or do) on their sites, mostly because of Section 230 of the Communications Decency Act of 1996 [0].
2. We don't know they haven't been served with a national security letter. DDG's protection scope doesn't cover you needing protection from the government, though. So we know using DDG != Google because that's the surveillance threat vector they're concerned with: literally not being Google (which they aren't).
2. We don't know they haven't been served with a national security letter. DDG's protection scope doesn't cover you needing protection from the government, though. So we know using DDG != Google because that's the surveillance threat vector they're concerned with: literally not being Google (which they aren't).
[0]: https://en.wikipedia.org/wiki/Communications_Decency_Act#Sec...