I strongly disagree. It seems to assume that everything is read as often as it's written which is not true. The best writing is written once and read millions or billions of times. Maybe it should be write 1/100th or 1/1000th of what you read. (But even this assumes that what you're writing is worthwhile, which for lots of people I think is not true).

There are details to Rule #6 I didn't include in the original post.

• It is measured in time spent. The idea is to spend at least one hour writing for every hour you spend reading. Reading your own work counts as "editing" and goes in the "writing" column.
• Looking up answers to specific queries for a predetermined productive purpose counts as "creating".
• Rule #6 is more important the smarter and more independent-minded you are. It applies to less than half the population.

Reading makes you smarter. But is also a passive conformist activity. Being smarter is advantageous. Being a passive conformist is disadvantageous.

Passivity

Consuming media created by others is a passive activity. You are not doing anything. I value doing over thinking. See Rule #3.

Except for some books in math and the hard sciences, there's no test of how well you've read a book, and that's why merely reading books doesn't quite feel like work.

―How to Do What You Love by Paul Graham

Conformity

Consuming media created by others is a conformist activity. You are running someone else's thoughts through your brain.

Reading, after a certain age, diverts the mind too much from its creative pursuits. Any man who reads too much and uses his own brain too little falls into lazy habits of thinking.

―Albert Einstein [LW · GW]

If you want to be Albert Einstein you can't just read his work. You have to copy. You have to steal. See Rule #11.

The utility of writing

You can have the best of both worlds by doing things and writing about your experiences. Writing isn't just the process of dumping preconceived thoughts into a keyboard. Writing creates ideas and forces them to be coherent. This creates value independent of whether anyone reads what you write.

If all you want to do is figure things out, why do you need to write anything, though? Why not just sit and think? Well, there precisely is Montaigne's great discovery. Expressing ideas helps to form them. Indeed, helps is far too weak a word. Most of what ends up in my essays I only thought of when I sat down to write them. That's why I write them.

In the things you write in school you are, in theory, merely explaining yourself to the reader. In a real essay you're writing for yourself. You're thinking out loud.

But not quite. Just as inviting people over forces you to clean up your apartment, writing something that other people will read forces you to think well.

―The Age of the Essay by Paul Graham

Creating art distills information. It is true that you do not get raw data from writing. But you do not get raw data from reading either. You get raw data from doing things.