Meanwhile, all the pages on https://wordsandbuttons.online/ with all the animation and interactivity are still below 64 KB.

This one, for example, https://wordsandbuttons.online/trippy_polynomials_in_arctang... is 51 KB.

And the code is not at all economical. It's 80% copy-paste with little deviations. There is no attempt to save by being clever either, it's all just good old vanilla JS. And no zipping, no space reduction. The code is perfectly readable when opened with the "View page source" button.

The trick is - zero dependency policy. No third party, no internal. All the code you need, you get along with the HTML file. Paradoxically, in the long run, copy-paste is a bloat preventor, not a bloat cause.