Silverfish and endermites don't make footstep sounds or subtitles

The bug

When silverfish (or endermites) move around, they don't make any footstep sounds or subtitles. There are sound events for footsteps (entity.silverfish.step, entity.endermite.step), but the game doesn't use them, nor does it use the default footstep sounds.

All other mobs (including blazes and withers on the ground) make footstep sounds, so this seems inconsistent.

Code analysis

Based on 1.11.2 decompiled using MCP 9.35 rc1

Silverfish and endermites override the method net.minecraft.entity.Entity.canTriggerWalking() to return false. This causes them to not make walking / swimming sounds and does not slow them down on slime blocks or causes magma block damage (see also MC-102267).

Additional updated code analysis can be found in this comment.