This is likely not the case for everyone but if there is a must have feature in iOS 17 it’s live voicemail translation and transcript of voice memos in text. Where I work people voice memo all the time and it’s annoying when you are unable to listen to it yet they want an answer lol
Also the new options for stickers as tap back is fun and there is some cool stuff with Live Photos you can do to make your own. And interactive widgets is, I hope, going to be very interesting.
But overall it’s a lot of very nice feature updates.