Comment by Grom_PE

For comfortable reading, I just had to figure out what on this webpage causes Chromium to drop subpixel rendering, and it's not this:

    html { -webkit-font-smoothing: antialiased; }

it's this:

    #TableOfContents { backdrop-filter: blur(3px); }

A panel that overlaps content only on narrow screens disables subpixel rendering for the entire text. Thanks Chromium. Not an issue on Firefox, btw.