The column-number switch on the site is a clever idea, but I don't think it works. The columns are limited to a fixed height (that depends on their number). The fixed height forces readers to scroll down each column and then back to the top to read the next.

The site should imitate newspapers either more or less closely. In either case, first limit column height to something like 80% of the viewport to eliminate scrolling within columns. The column switch can select column width as a fraction of screen width.

More closely: when the content is too long for one set of columns, split it into multiple newspaper-style pages. The reader scrolls vertically through the newspaper pages.

Less closely: use columns arranged side-by-side in a horizontally scrollable container. The reader scrolls vertically to reach the container, then horizontally through the columns.