You may be interested to read Reviel Netz's Scale, Space and Canon in Ancient Literary Culture (2020). While I disagree with his claim that there was a "single, dead" canon (p. 56) with no local variation that was fossilized at Classical Athens, he has some interesting things to say about canonization:
"The dynamics of canon formation are not the || positive process of the 'construction of the canon,' imagined by so much of contemporary scholarship in the humanities. Canons are formed through a negative process of loss." (pp. 206-207)
You may also wish to read pp. 215-216, where Netz claims that the canonical lists of 9 Lyric Poets, 10 Attic Orators, etc., actually expanded the (already established and very narrow) literary field, rather than being a selective canon.