The organiser's problem is not the couple's problem
A wedding is a private distribution to a known list of relatives. An event is the opposite: a public-ish distribution to a crowd whose contact details you mostly do not have. You cannot email the photos to people whose emails you never collected, and you should not be collecting them just to send a gallery.
That single difference decides everything else on this page. Your distribution channel is not a message thread — it is signage, a Slack channel, a class group, a newsletter, or a slide at the end of the closing talk. So the link needs to survive being read off a wall by a stranger, on a phone, on venue wifi, without a sign-in step in the way.
It also means your link is effectively semi-public from the moment you print it. Plan for that rather than pretending otherwise — the consent section below is not boilerplate, it is the part organisers most often wish they had read first.
If your audience is a known list of people you can actually message, the wedding album workflow is a better fit than this one.