The contents of webpages are largely the same.

HTML code, CSS, Javascript, Images.

In this case, they are static elements, which can even be cached locally to share more easily.

If someone wants a massive build system to render a static HTML page, that's on them, and their personal interpretation. Increasingly, and maybe more often than not, there is more than one way to get the same outcome.

The fact that there's hundreds of downloads for a single web page is up to the constructor of that page. Still, these things can be reasonably cached. For example, host it on the Pi, then put a cloudflare in front of it or something.

The Pi Zero might not be for you, or easy to try to undermine. Which criticisms would go away if it was on a regular pi?