I'm not sure the error potential is much higher than with average teachers, but I guess it depends on the domain. For coding the error rate is lower than a typical teacher right now.
I suspect we'll soon figure out an effective way for LLMs to look-up reliable references to confirm their answers, which should improve the situation drastically. As they are now most LLMs are very barebones. An educational LLM could e.g. connect to the university textbook library and use that to verify its answers.