If you've got an Apple Watch, you don't have much of an option but to stick with the 16. I went from a 13 Pro to a 16 and I'm quite happy with the decision. I do own a Pixel 7A, which I use at home for social media, and while I see the appeal of a Pixel phone and the Android OS, but the overall iOS experience is irreplaceable for me.
I think the biggest question would be, do you plan to keep your Apple Watch? If yes, your choice is clear as daylight.