The iPhone 16 also used aluminum
Only the pros went from titanium to aluminum for thermal management at the expense of looks.
iPhone 17 is definitely a big improvement from 16 with 120hz refresh rate, bigger screen, much better ceramic glass, much 8 more hours of battery. and better selfie and rear cameras.
The pros while better performing look less premium than the titanium from the last 2 years.
The Air with the titanium frame and super thin design is the rich people now