If you are displaying something in two or more columns, you may want to change that to as little as one column when using some of the largest Dynamic Type settings to keep the text readable.

Two examples of the Weather app. The first one is using the Large (default) font. It displays information like UV Index, Susnet time, Wind or Rainfall in two columns. The second one is using the largest font size available and the UI switches to one column so there's more room for text and it can go side to side, making it much more readable than if it had just the space of half the screen for such large font sizes.