The font is so small I had to zoom in 3 times to 150% get a comfortable size. And then zoomed in one more time to 175% to make the font a little thicker - as you say, due to the light color. The irony made me giggle a little.
I wouldn't mind too much if the website styling didn't break zooming in the browser. The paragraph width is fixed as a percentage of the viewport, which means zooming in only makes the font bigger, keeping the same narrow column for its contents.
On the whole the HTML and CSS on that blog are a mess though.
Firefox's Reader View helps here by bypassing the author's styling completely.
Fully agree. That's why I generally browse internet on mobile in Opera which supports text reflow and force-zoom, contrary to Chrome which only supports the latter.