“What makes glyphs hard” Another reason is hinting. Traditional text renderers like FreeType are aware of the pixel grid and they adjust the curves slightly, snapping them to that grid. For all methods in the article quite hard to do on GPUs.

“Chinese, Japanese, and Korean have tens of thousands of glyphs, and baking all of them at several sizes is a memory disaster” One possible solution is dynamic atlas built on CPU for visible glyphs only.

“The distance-field panels notch, where interpolating between stored samples no longer matches the true curve” Can’t it be fixed in the shader, using screen-space derivatives of the SDF? I think in theory, SDF value for pixel center combined with screen-space gradient vector of that number delivers enough data to compute partial coverage for the pixels on the edge.