I think he's going for a metaphor about groups versus individuals. There are other gray dots around the red dot. Software is a group effort, but made of individuals. Something, Something.

FWIW I see the red dot only at the top of the page, flashing slowly. It does not annoy me, in fact I only discovered it because of your comment.

On desktop, it's fixed to the left of the story, pulsing along the entire time you're trying to read. If you are like me, it will annoy you. I had to switch to reader mode.

From what I can tell, it marks the article you're on. There are other light grey dots with other article names in it.

Yeah. This one shows a graph:

https://www.thetypicalset.com/blog/grammar-parser-maintenanc...

Solid red dots are articles you've visited.

Turning off Javascript made the dot go away.