If we’re talking about freshman CS 101, where every assignment is the same year-over-year and it’s all machine graded, yes, 90% is definitely possible because an LLM can essentially act as a database of all problems and all solutions. A grad student TA can probably see through his “explanations”, but they’re probably tired from their endless stack of work, so why bother?

If we’re talking about a 400 level CS class, this kid’s screwed and even someone who’s mastered the fundamentals will struggle through advanced algorithms and reconciling math ideas with hands-on-keyboard software.