@matt
It’s a tough call, and I’ve struggled with it too. I think ultimately it is on us to fix, though philosophically I don’t love that conclusion.
I suspect part of the problem on this page is that the h3 headings are very short, which makes the font size difference less apparent.
One solution that works well on this page to my eye is to indent the h3 and add a bullet:
h3:before {
content: '•';
color: gray;
margin-right: 1ex;
}
(Maybe bad for screen readers though?)