Any mods that implement a secondary player renderer to be displayed when in first person doesn't play any animation (with playerAnimator installed) when holding guns for the renderer display itself, unless switching to third person.

This affects the Yes Steve Model mod specifically for the vanilla/standard model type with self model and self hands disabled in the config
Extra Player Renderer also happens to be affected, I suspect it's an incompatibility for vanilla models

Note that this is for the latest 1.18.2-1.1.4 hotfix release version of TaCZ