Not really techcrunch's fault, that. It's because facebook comments are loaded via an iframe, browsers probably don't transfer the "outer" zoom to the "inner" one all cases.

I was under the impression that all browser already switched from "increase font size" to regular zoom (as Opera had for example). But yeah, Chrome seems to broken in this regard. It's not as horrible as Firefox and IE used to be, but still... I'd file it as a bug report to your browser vendor.

It's not just on TC. I keep meaning to get around to writing a Chrome extension to fix that on sites for myself.

You can configure minimum allowed font size in almost any browser.