Pretty sure that every good writer can make it, though. Perhaps the mediocre writers have an advantage if they have relations. No doubt a lot of awfully bad books are being published every year, and some even are successful.

I used to think about this, "only people with relations can make it". When I got older I realized that if you care about some subject, you will probably end up making relevant connections on the way.

And I also think this way of thinking about privilege is self-defeating. If you don't have "privilege X", find another way.

Some writers now got rich without ever having an agent, self-publishing.

I'm sure people will find some other alleged privilege they had, which allowed them to do that. That's not the point.

If you are dead poor and have no connections whatsoever, you have the "privilege" to write authentically about being poor.