The last several iPhone generations have all be strictly incremental, including the iPhone 16. IMO, if you have an iPhone 12, 13, 14, or 15, you have no good reason to upgrade to the 16.
The Camera Control button is the worst new feature this year. It's ill-conceived. It's totally unnecessary. In fact, it has killed my desire for any future upgrade. I don't want this button on my phone. Period.