Here’s a perspective on UK and Canadian newspaper coverage of the First World War.
From the British Newspaper Archive, 1911 to 1919, counting occurrences of the terms Ypres, Somme and Vimy. Ypres was dominant in 1914 and 1915, Somme thereafter. Vimy gets its most mentions in 1917 with more in 1919 than 1918. Summed over the period Somme is mentioned more than Ypres.
Canadian newspapers digitized by newspapers.com shows Ypres dominating in 1915, Somme in 1916, Vimy showing strongly from 1917, leading in occurrences in 1919. The absolute numbers are less for Canada than the UK reflecting population and the extent of the database.
The validity of these data depends on the quality of the OCR.