From Bertram Brooker: Life and Work by James King:
Brooker’s relationship with the Group of Seven was complicated and conflicted. He was drawn to Lawren Harris (1885–1970), in particular, for his belief in the spiritual in art, but did not fully ascribe to the Group’s goals. In October 1929 Brooker publicly questioned the Group’s political agenda. He wrote that: they “are modern only in the sense of being contemporary: they are not ‘modern’ in the generally accepted sense of belonging to the special tendency in painting that stems from Cézanne.” Brooker almost certainly saw himself as part of this “special tendency.” For him, the modernist elements in the works of members of the Group were not truly avant-garde. They may have been superb colourists, but they were not what he considered cutting-edge.
That quote is from Brooker’s “Seven Arts” column of 29 December 1928 (I’ll try to find the full original). What a perfect distillation of the problem with the Group: “modern only in the sense of being contemporary,” not modern “in the generally accepted sense of belonging to the special tendency in painting that stems from Cézanne.”
Brooker was remarkable: artist, novelist, graphic designer, advertising executive, and more. For a recent deep dive into one angle on twentieth-century Canadian art, with a chapter on Brooker, see Adam Lauder’s Out of School: Information Art and the Toronto School of Communication.
(Brooker and the Group were friends, and all members of the Arts and Letters Club of Toronto.)