No. The elements are not used by Webflow anymore. Everytime I changed the behaviour of the grid within Webflow, it creates a new ID for this grid-element. However, the generated CSS still contains the old IDs. So Webflow is not doing it’s housekeeping, and leaves old IDs in the CSS. This will bloat the CSS with time. So from a simple 30k CSS you get easily to a 1MB CSS if you are doing a lot of grid changes in Webflow. Others had the same issue: CSS Grids Exported Code - #5 by webdev
Note: the grids are within a symbol. Maybe this is the problem?