So guests can't browse everyone's photos like a normal public gallery? Not even a little?

Correct — through the standard guest experience, each person sees only the photos matched to them. There's no "view all" toggle hiding in the corner. That's the entire privacy architecture: it's not that browsing is discouraged, it's that it doesn't exist for guests. If you genuinely need someone to see everything — the couple reviewing all four thousand frames, a client picking selects — that's what the full-access link is for. One master link, shared sparingly, solves the legitimate cases without compromising everyone else's privacy.