No better clarification than the author! In my mind, I was thinking of just the web framework UI-for-CRUD comparison, where Next.js is supplanting what Rails is typically used for (like your Dashboard / GUI, and most of the core webapps for the previous 2010 Rails co's), but fair enough, you're probably leveraging a lot more of your own PostgREST, triggers, functions, & webhooks than a typical backend Next shop.