In the viewer, press '/' and configure hinting to full, or modify the source in gm/fontations.cpp and call SkFont::setHinting(SkFontHinting::kFull) or kNormal.
Thanks for the reply. I was able to play around with the settings there, but even when enabling full hinting it's still only hinting vertically (I think this is what it was doing by default, as in my screenshot—this is similar to what the FreeType v40 hinter does, which is used by default from 2.7 as mentioned in my first post).
EDIT: looking into the FreeType code, it looks like the v35 mode turns on the `NO_SUBPIXEL_HINTING` flag [0], which might have also been ported over to skrifa [1]? Though there are "(always enabled)" comments throughout the code suggesting that it can't be configured.
Maybe later I'll try forcing the option and see what happens.