Husks and strays, wither skeletons lack walking subtitles they make the sound (if you listen hard or turn up the volume), but the subtitles do not appear.

Steps to reproduce:
1. Turn on Subtitles.
2. Spawn one of the two aforementioned mobs
3. Push said mob (through pistons, flying, etc.)
4. Listen and watch.
The sound plays, but no subtitles are heard.
The same thing applies to using /playsound minecraft:entity.husk/stray.step

MC-103177 presents this same problem, it is marked as fixed, however in this version, that's not entirely true. I believe it's more efficient to make a new report than to comment on an old one (though if I'm wrong, please say so.)