The three-column layout is often treated as a relic of the early web. That judgment usually comes from layouts that used columns as decoration rather than structure.
A useful column has a reason to exist. Navigation benefits from a stable home. Long-form reading benefits from a controlled measure. Context benefits from proximity to the document it explains.
The web has changed, but these needs have not. The question is not whether a page has three columns. The question is whether each part of the page helps the reader understand where they are and what to do next.