I just finished Photopia for the second time, almost twenty years after my first playthrough. I worried that time or perspective would change my opinion, and while that did indeed happen, it remains a treasure I will still recommend to anyone who delves into the world of interactive fiction.
When I first played I was about 20 years old and was mostly moved by the big dramatic moments. Like others have mentioned, time has led me to find these somewhat manipulative, lacking depth. The character of Alley in particular doesn't move me any longer, though I reject that she is a Mary-Sue. We don't see her flaws, though I believe this is because we only see her through the eyes of others who have no reason to highlight her flaws. On this playthrough then I was moved by the characters around Alley, her parents especially (perhaps being the parent of a daughter now helps that). The best parts of Photopia are the ones that don't move the story, where you learn more about everyone through the conversation system or by examining the world around you. The only part I actively disliked was the scene from Alley's suitor, who is nothing but a trope here.
Beyond the characters, I am still amazed at the technical skills on display. The dynamic maps during the bedtime story sections are amazing. Cadre also does a wonderful job of pushing the player through the game at the perfect pace in order to tell his story. While this could have worked as static fiction, I believe the medium improves immersion.
Even with its now recognizable flaws, I remain very fond of this work and will hopefully play it with my children when they are old enough.