The ORM works against a relational database. The relational databases that Django supports are not distributed, right?

May depend on your workload and what you mean by 'distributed'... there are some scalablleity options for postrgres. There are backend drivers for Oracle and MS SQL as well, but I have never used either and I'm not sure just how good they are.

But there is nothing that I am aware of inherent to the ORM itself that prevent horizontal scale.

You scale your app server out and your database server up. You can have 100 django servers hitting one database with a read-replica, for example.

Depending on your workload, this is often a great way to scale and pretty typical for Django. In most cases your app servers will saturate way before the database does.

Thanks for this. Yes this actually makes sense. I considered that a given, though, since scaling the Django app is trivial since it is stateless. Scaling the state is always the difficult thing.

You can get horizontally scaled eventually consistent on reads just fine on postgres/mysql via replication. There are also write scaling options.