Running a Google Nest Mini with the Google Home App onan iPhone

This is what my AI says about controlling a Google Nest speaker from an iPhone:

The only minor difference between using an iPhone and an Android phone is that you can’t set Google Assistant as the default voice assistant on your iPhone.

Does that mean the nest mini won’t be able to read my Gmail and What’s App messages out loud?

My AI suggested buying a Samsung A16 phone (unlocked) would be the cheapest and most effective way to control a Google network in my home. if I want