Note, in the interest of academic honesty and historical accuracy, I will preface my answer by acknowledging that it constitutes original research and is purely anecdotal, though I believe it is worth sharing because of its relevance to the question:
I can't produce any writings for you, per your question, just a firsthand account: According to my grandmother, EVERYBODY noticed the transition from Gros Michel to Cavendish bananas. She was living in California's San Joaquin Valley at the time, the wife of a fruit farmer, so perhaps she has a more sophisticated taste for exotic fruit than most. But she claims that when the local supermarkets switched to Cavendish, a lot of customers (that were also her neighbors) complained that the new bananas weren't as big or as sweet and flavorful.
First of all, visual appearances: Gros Michel bananas tend to have a shorter, more pronounced curve near the stem and then a much longer, more uniformly slim body than do Cavendish. Overall, according to what my grandmother said, they appear to be the bigger fruit. So perhaps consumers felt they were getting shortchanged when Canvendish first showed up on the shelves, price-per-pound unchanged.
Secondly: Taste and flavor. Have you ever had banana-flavored candy? My grandmother swears that the flavor is inspired by that of Gros Michel bananas, not Cavendish. Apparently, that's actually a myth (though there is a well-founded correlation between the flavorings). Gros Michels did in fact taste much sweeter and had a more pulpy texture than Cavendish. The latter is often described as more bland, the weak taste being further dominated by the Cavendish's relative firmness and fibrous texture.
This is just one person's story, but it hopefully provides some insight into the impressions of the average American consumer during the transition from Gros Michel to Cavendish.
