Siri responds only with text
Siri responds only with text if in car or no wifi. For example, in the past when not on wifi, I press the home button and ask to send text to John and Siri would ask what I want to say, or I could ask read text from John and Siri will speak his last text. But now, Siri only responds to me in text when not on wifi. I have always kept cell data off with a few exceptions on certain apps since I don't have unlimited data. I don't think I made changes there.
iPhone SE, iOS 13