I installed the new iOS beta on an iPhone 7, and I don't see the new details in maps, and I don't see the new Live Text features in photos / camera.
I didn't see anything in the release notes about required hardware...
iPhone 7 limited functionality?
The new Maps is only rolled out in a few countries and states currently, so you may live in a region where it’s not rolled out yet. Live Text most likely requires the Neural Engine, so iPhones with an A11 Bionic chip or later (iPhone 8, 8 Plus, X and later)
Hi! According to Apple’s iOS 15 preview page (under All New Features and the footer at the bottom of the page - Point 1), Live Text requires an iPhone with an A12 Bionic chip or later. The iPhone 7 has an A10 fusion so you’ll need an iPhone XS/XR or later to test Live Text.
as for the maps, the Globe and detailed city features for London, SF, etc. shown today also requires an iPhone with A12 Bionic or later (see same point mentioned above (as well as Point 3 in the footer for info on the detailed cities feature))
hope this helps! 😀
Live Text requires the Apple Neural Engine which is available on iPhone devices somewhere around 2018 and newer.