> less likely than a _single_ party being pressured or even a single party's infrastructure being hacked.

Since Obscura uses a custom QUIC-based (?) protocol, you'd need to use their custom made (open core) app to pay & register with both Obscura & Mullvad. That means, all your apples are in their app-basket, which is built entirely by a single-party?

Private Relay, otoh, seems like a 3 party setup (Apple, Cloudflare, Akamai)?

See also: https://news.ycombinator.com/item?id=43017140