Your mind is a living collection of your own ideas, and a history of their significance to your prior life. Not a dead library of pointers to other dead libraries.
Books are great. But you shoudn't outsource your brain. The learning happens when you think for yourself. Reading is good. Thinking about what you've read is even better. But don't stop with the summary! Go further. Apply it to your context. Try it, it's fun.
What I mean is I f someone is already remixing, they’re already writing about what they read and probably don’t need advices from articles like this because they already read differently from what the author imagined.
On the other hand, the article encourages people to write about what they read outside a formal academic context, and most people don’t have that habit.
To put it another way, writers don’t need rationale to write. But writers are not the target audience.
I'd say it's yours. In that frame, there are lots of ideas.
Lets assume there are 10 000 known ideas. Then there's 10^8 combinations of two ideas, and 10^12 combinations of three ideas. That's a lot of ideas, even for the internet! I bet not all of them are named. And different people are going to frame ideas differently.
I also believe trying to form your ideas in reference to existing knowledge is a great way to learn existing knowledge.