You are not alone! This is also how I run coding interviews - I have absolutely passed candidates who did not actually complete the described problem. I always

You are not alone! This is also how I run coding interviews - I have absolutely passed candidates who did not actually complete the described problem. I always inform my candidates that we want to have a conversation about the problem and its solution. I also deliberately pick questions that are going to need thought and some design, specifically to spark that conversation - talking about reversing a list gets boring pretty fast. The issues people have with coding interviews are more about the interviewers than the questions, honestly.