This seems like a good discussion but its author (Cory Doctorow) has a long-held grudge against Google. See his short story "Scroogled" (https://craphound.com/scroogled.html) from 2007. Not exactly unbiased.
What is it with sci-fi authors being so uniquely insufferable now that they’re all opining publicly on every topic under the sun? It’s a fascinating phenomenon that I haven’t seen anyone investigate yet in depth. Would love to read an article about it.
TL;DR: The "economic mistake" is allowing monopolization through vertical mergers (taking over parts of the supply chain both upstream and downstream).