Will people continue to install mobile apps? Or are we all going to be living in AI assistant walled gardens, telling it "let's order groceries" or will it just do things for us so we're not ordering things manually?

For the broader people (outside of tech, everyone else), what will the next 10-20 years look like?

Most people outside of tech circles don't use AI, at least not on purpose. Gemini enhanced search results are about the most they will use, and from those I've talked to, some didn't even know that it was "AI" which is mind-blowing.