Mullvad operates out of Sweden. Unlike proton, mullvad doesnt have to respond to court orders. proton gives up user info thousands a year its right on their transparency page.
What Mullvad apparently don't have are data-plane logs. But then, surveillance laws mandate forceful & secret compliance in certain cases (Mullvad may be exempt but who knows: https://news.ycombinator.com/item?id=43018290)