I don't trust an LLM to answer accurately on topics that I don't already know well. It's useful as a multiplier on things I do know, since I can correct mistakes and spot hallucinations, but if it's something I don't have knowledge on it seems like it might be confident but incorrect and I wouldn't notice or check it's answers.

I'm pretty sceptical of people using it to learn a foreign language or something they aren't familiar enough with.