update_simulation have the exact same docstring. What is the point/when to use each one?
this is a bug in the documentation, thanks for reporting, will fix it.
reset_simulation will remove all objects from PhysX SDK simulation and will reset transformations in USD to original state where simulation started (see start_simulation), in general this function is only useful if you intend to step simulation yourself from python and want to reset the transformations back where the sim started
update_simulation will step the simulation by one frame using the provided time step and the current time (used for USD animated objects, that can be kinematic in physics)