They're handy for conversational type questions where remembering previous questions is important, but that's about it. That's not usually important though, and can easily be accessed through a website instead.
Being able to ask questions about the currently playing YouTube video has been phenomenal for me, it's the ultimate anti-clickbait.
Other than that, no, not really.
Being able to questions about images could open some great automation possibilities, but I'm very much not stoked about sending images to Google/OpenAI/whatever, so until those models with vision capabilities can run locally on a phone, it's a dead end for me.