The main benefit is that in XML/YML files we have common syntax (i.e. core.controller, form.pre_bind) that properly namespaces event names (before: onCoreController was ok, preBind was not).
On the other hand in PHP land we also have namespaced events, CoreEvents::controller, FormEvents::preBind, before it was Events::onCoreController, Events::onPreBind, we now have more context.
