That pattern may be reasonable for "Are you sure" kind of requests for actions that the user explicitly wanted - because then there really is a sane default; we

That pattern may be reasonable for "Are you sure" kind of requests for actions that the user explicitly wanted - because then there really is a sane default; we expect the user didn't click on some button by accident. But it's not reasonable to portray questions that are asking the user to agree to something they did not explicitly want; that's just trying to trick the user to make the annoying popup go away by clicking the big button. There's no sane default here, so none should be preselected (and ideally, the layout of confirmation dialogs and agreement dialogs would not be identical in the first place). It's a dark pattern, and I really doubt it's accidental.