That article is talking about unitys new strand based hair system that can import alembic hair from other programs. I’m not sure if there’s any tutorials on it yet
Alembic is a data exchange format. When you hear about an “alembic simulation”, it usually refers to importing a baked simulation (stored in an alembic file) into the engine. This is not actual simulation but basically a “video” of it that you can play back. Not interactable in any way, and won’t react to other objects in the scene, but much cheaper than a simulation.
Unity’s strand-based hair solution (which has been already available for quite some time, here’s some resources to get started: Get Started with Hair Simulation - Unity Learn) uses alembic to import static groom data (guide hairs) into the engine. Then, it performs an actual simulation of the hairstyle/groom defined by that data.
Note this is actually quite advanced stuff, it’s fairly easy to get terrible performance out of it unless you know what you’re doing.