Whether the source is something like stepup or Artifacts running shoes (actually not this one, must have been some other incompatibility), other mods step height does not function while Apotheosis is installed.

Not totally sure if any of these are relevant but figured I'd put them here:

And the ways the two mentioned mods do it:

https://github.com/spoorn/StepItUp/blob/main/common/src/main/java/org/spoorn/stepitup/mixin/ClientPlayerEntityMixin.java#L32

https://github.com/ochotonida/artifacts/blob/1db8c1eae7bc546ce295232e37435df6ddae7deb/src/main/java/artifacts/item/wearable/feet/RunningShoesItem.java#L22 (not this, actually)