These posters have a very well-defined structure. It definitely feels like tabular data and tabular data is one such case that the disposition of the information extrapolates the realm of graphic layout and starts hinting on the meaning of data and how various chunks of data relate to each other. The abuse of tables as structural elements was, and still is, very harmful to web accessibility. However, blindly replacing tables for div tags does not help to make code more semantic. List elements are a great solution for collections of similar data, but ULs and OLs do not define any kind of relation between this data.