But articles shouldn't have to teach readers all the background needed. Otherwise even a well written article would get a lot of bloat. Even linking other guides would require some context, and the total breadth of knowledge could be quite high. I could agree if there was to be a brief "areas you should know about" with a few keywords.

There are some areas where Hacker News might uniquely shine in answering questions, but "what are dataframes" isn't one of them. If someone sees "dataframe" and is confused, they have all the opportunity to search up "dataframes 101" and get up to speed.