I don't relate much to the first paragraph though. You don't have to include a module to use arrays. I'm mystified by the implication that data integrity, normalization, and ad-hoc querying are useless for "modern application development".
Looking into it again now it seems I was confusing Arrays for Hashes, with regard to the hStore extension.
The application is in charge of what data goes into the database. It is performing sanitisation, validation, returning errors, all of that before persisting data. I don't want to have to deal with errors from the database nor do I want to have to manage data integrity from two separate locations.
I want to be able to tell the database to store something and it stores it modern development frameworks can handle data integrity stuff.
Separate that out and share it between however many applications you want you should be able to swap out data stores not be confined to them.
I've also never made an application that doesn't eventually want to do something that the ORM I'm using doesn't know how to do, at which point it makes a lot more sense to interact directly with the database than to shrug my shoulders and say "I guess I can't do that".
Maybe my applications just aren't "modern" enough.