For me it was the camera + price combo. The Samsung cameras are probably better on the flagship phones but the prices for those phones are insane. iPhone price is obviously even worse and I really don't like the camera and how iPhone applies edits automatically, even to the RAW files.

I do a lot of photography and the Pixel 6 Pro with the wide angle lens plus dedicated Telephoto 4x zoom lens covers like 90% of my needs. Other than true long exposure, super low light night shots, macro, and astrophotography, my Pixel 6 is great.