Subtitles for mobs walking are inconsistent. Examples:

When a camel walks, the subtitle says "Camel sands" (if it walks on sand) or "Camel steps"

When a llama, Piglin, or panda walks, the subtitle says "Llama/Panda/Piglin steps"

When a goat, frog, mooshroom, ocelot, creeper, spider or player walks, the subtitle says "Footsteps"

These are the ones I tested. This seems inconsistent, either the subtitles should always say "Footsteps" or "[Mob] steps", except in unique cases (e.g. "Rabbit hops").