Well, with rapidly evolving speech and sound recognition technology, not long. There are a few tiny details to figure out here, but overall, AI is already really comfortable with audio processing, analyzing, and processing. In this article https://www.alltheragefaces.com/... you can learn more about some minor challenges with this technology, but also, ways to get rid of them. So, soon Artificial Intelligence will be all over our voice assistants.
You can already kind of do this.
There exists GPT-3 already, and there is an API for it.
If you connect it to a speech recognition program or AI (there are plenty of open source ones) and send to the GPT-3 API, and then have a text to speech program (also AI lol) give an answer, then you have a product already.
May need to do some prompt tuning so you get "chatlike" answers rather than a wall of text though.