For very simple JSON data whose schema never changes, I agree.

But the more complex it is, the more complex the relational representation becomes. JSON responses from some API's could easily require 8 new tables to store the data in, with lots of arbitrary new primary keys and lots of foreign key constraints, your queries will be full of JOIN's that need proper indexing set up...

Oftentimes it's just not worth it, especially if your queries are relatively simple, but you still need to store the full JSON in case you need the data in the future.

Obviously storing JSON in a relational database feels a bit like a Frankenstein monster. But at the end of the day, it's really just about what's simplest to maintain and provides the necessary performance.

And the whole point of the article is how easy it is to set up indexes on JSON.