She's busy opening presents
The guest of honour is usually on the sofa under a pile of tissue paper, which means she's in every photo and has taken none. Her friends catch her face when the tiny knitted cardigan comes out, and the moment someone guesses the due date to the day. With a gallery, she gets to see all of it afterwards.
A small party with a lot of phones
Baby showers came over from America and have settled in here as an afternoon at home, in a café or in the private room of a restaurant. It's a small crowd taking a lot of photos, and they end up split across different group chats. One gallery collects them, videos included, so the clip of everyone measuring the bump with string survives at full quality.
The sister in Canada wants to see too
Showers are for close friends, but grandparents, the sister in Canada and the friend who's due next month and can't travel all want to see. Send them the private link and they can look through the photos as they arrive. The pages open in whichever of our 15 languages their phone uses, so Nani can read it in Hindi and Babcia in Polish. It's a private link, and the gallery is never on Google.
It can keep going after the baby arrives
A gallery has no cut-off date: the link works for as long as it's online. So you can share it again once the baby's born and let the first visitors add their photos. It's the same gallery with the same room for 3,000; if you'd rather keep the newborn photos separate, you can start a second gallery, paid for on its own.