Seemed like it would be interesting to read, but I slammed the back button once the butterfly (wtf), blur effect, and thin grey font on a white background overwhelmed me.

Agreed. The correct text color is the one of the titles. The paragraphs are too gray, they have not enough contrast. Place a sheet of paper from a book or a magazine side to side with that page and the text on the paper will be much easier to read 99.99% of the times. Is there any irony in that? Given the subject of the post, maybe not. It's a demonstration that hundreds of years of paper typography yield a better ergonomy than 30 years of the web.

I slammed the reader-mode button, which unfortunately killed the videos.

Not having looping/procedural animations in your articles is an accessibility feature. People with ADHD simply can't read blocks of text if there's visual noise flitting about everywhere.

I liked the fun animation, but I agree that the text should be darker for readability / accessibility.

Design choices like these tend to negatively influence my opinion of whatever I'm about to read. That's a shame, too, because the demonstration that followed is a very rare use case for AR and AI that didn't make me roll my eyes.