Writing seems to more of a tool to refine/coalesce thoughts

That's the idea behind "Getting Things Done" (GTD)

This is actually good advice.

Writing down things makes it much easier to move forward to the next project of the day.

Probably various a bit from person to person.

I recoiled at that a bit too, but I think what they mean is similar to how some games can "only be played once". Best example of that is Outer Wilds, where attaining information is the goal of each gameplay loop. Once you've acquired that knowledge already, the fun of acquiring it can no longer be experienced since you already know what the "next step" is.

I think their point is clear if you read the rest of the sentence: “… given the number of compelling works and the limited time available to us”.

Yes, it’s the OP’s choice, it’s their information diet. You COULD read the good stuff over and over, but you risk falling behind the flood. This is their approach to keeping up. It makes me a little sad, sure, but as a practical solution I get it.

I certainly don’t use this approach to literature. I’ve reread my favorite books a few times over the years (Cat’s Cradle, White Noise), but I’m sure that’s not the kind of thing OP is talking about.

Same. I feel a strong urge to highlight a paper's section on Methodology now, but no idea why.