What does "That’s pretty much all I read"?

Question

I've come across with the phrase below:

That’s pretty much all I read.

I know "pretty much" means almost completely[1]

But I don't understand the whole meaning of the phrase.

Does it mean

All I read is aproximately that book?

The fuller text:

Perez enters the room and speaks to her in a low voice. “I’ve just remembered something. It might be important.” She nods. “You wanted to know if I or Wilcox had ever heard of the author Candice White. I thought the name sounded familiar but I couldn’t place it. I thought maybe it was someone my wife read. She reads a lot of books.” Sorensen nods her head again impatiently. “Yes?” “But actually I’ve read one of her books. She wrote a true crime book a few years ago that I quite enjoyed. That’s pretty much all I read.” “Is that so?” Sorensen says. “What was it called?” “I don’t remember exactly, but it was about that school principal who murdered one of his students.”

An Unwanted Guest by Shari Lapena

[1]https://dictionary.cambridge.org/dictionary/english/pretty-much

Answer 1

She wrote a true crime book a few years ago that I quite enjoyed. That’s pretty much all I read.

• "That" = true crime
• "pretty much" = almost completely (as you said)
• "all" = the entirety
• "I read" is the present

So it means:

True crime is almost completely the entirety of what I read

or, to rephrase:

When I read books, they are almost always "true crime" books

---

Note that the "that" in your quote almost certainly refers to "true crime" in general and not to that specific book. This is because the "I read" is present, rather than the present continuous "I'm reading". It is unlikely that someone constantly repeatedly reads a single book, unless they are extremely dedicated to it for some reason (such as a devout Christian who only reads the Bible, or an obsessive quiz lover who only reads the encyclopedia).

Answer 2

You are being misled by your paraphrase of pretty much, namely "almost completely".

Consider the following imaginary conversation.

Detective: So, you came in the service entry door, turned on the kitchen lights, and saw the chef lying face down on the floor with a knife in his back.
Suspect: Pretty much.

There, "pretty much" means "That's the gist of it" or "There is nothing significant to be added" to that account. Anything that would be added would be very trivial, hardly worth mentioning.

So, when someone says "Murder mysteries are pretty much all I read", the meaning is "There is really nothing else to be added" to that assessment. It's possible that every once in a while a biography or a travel book might be read, but in the overall scheme of things, murder mysteries are the speaker's regular fare, and those other genres occur so rarely they're not worth mentioning.