[exiguus]

Personally, I know several databases where single tables have +500GB and the database has +100TB. With this huge databases the restore and backup process over network become indeed a bottleneck. So I can agree with the author. Also, the author does not say that they can't start with a single database server and just read replicas and max hardware out. Real world use cases with +100TB I know about are Stock Market, Traffic Data, Warehouses, Analytics and Monitoring.