Potentially? I have an iPhone 15 Pro now, which I got both because it was lighter than previous equivalents, and was the first (?) with direct-to-satellite, which I definitely value. I know I can get ~5 days of navigation (but not reading) out of it, which is one of the reasons I don't take a backup battery (the solar panel isn't a single point of failure; but of course the phone still is for nav, so still need a minimal paper map and a compass). I only spend a couple weeks a year backpacking so I wouldn't choose a phone purely based on that; but if I were in the market for an update this cycle I'd consider it.

Edit: Looks like the Air is 165 g, vs 187 g for the 15 Pro; not even an ounce difference. A bit more compared to the 17 Pro (206 g); but I probably just hold on until Russia collapses into a new metastable state and we can get bulk titanium again.