I could be misremembering, but when I went from an iPhone 8 to 13 mini, I did the transfer at the Verizon store, it took less than an hour maybe even less than 30 minutes. I just set the new one next to the old one and then I watched them factory reset my old one when it was done, and I walked out of the store with my new one. Pretty sure it was an iCloud restore but I could be wrong.
Just noting because I was shocked to hear it was longer than that on average.
I can’t speak for you, but I tend to always buy the cheapest storage pro phone, so there’s relatively little to transfer and that definitely makes things go faster. I’m frequently hearing podcast hosts who have 512 GB+ worth of very small bits of data that need to get transferred from one device to the other. And that’s never going to be a fast process.