My smartphone needs to have a good camera to capture all of life's moments. My kids doing things I want to let others know about, or record a memory I want to look back on.
My camera on the other had is for expressing myself. Picking it up to do something, or go somewhere, I want to capture with my self-expression. Like painting a picture or making some music, this is my art.
This really resonated with me. Of course, you can do artistic photography with an iPhone, and of course, you can capture candid moments with a full camera, but this distinction landed perfectly with how I use my cameras.
Here's a picture I took on my iPhone:
No big deal, just a photo of my dog as I was scratching his belly. It's a bit compressed in this post, but it looks very crisp and clear and I'm happy that I was able to nearly instantly snap a photo that is in focus and has all the details I need. My big camera could have done this and produced a better photo, but it is not always on me, and it is far more likely to miss focus or have a wrong setting for the exact moment. The highs are higher, but the lows are lower, especially when randomly snapping a photo.
But there are times where the big camera is better. I went to my wife's grandma's 100th birthday party around Christmas and took the big camera because this was a big event and we wanted to have the best photos possible. Could I have shot on the iPhone? Sure! Could I have used portrait mode to simulate a similar style? Of course! Did I have to edit these photos to get the colors/brightness correct in a way the iPhone would get mostly right automatically? Yup! But my Canon EOS RP was able to get higher quality photos and now we have an album with hundreds of photos that look great and will help us remember this literally once-in-a-lifetime event forever.
We always talk about "does gear matter?" and I think yes, absolutely gear matters. You can, of course, do basically everything with your phone, and many people do, but I don't think it's fair to say there is no difference, or that the differences don't matter.