PluginManager.registerEvent() creates TimedRegisteredListeners if timings are turned on.
TimedRegisteredListeners timings are ignored since EventExecutors now make their own timings when registered from JavaPluginLoader.createRegisteredListeners().

TimedRegisteredListeners used to formulate their Timings report in execute(), which is bypassed in favor of executeSpigotTimings(). The only solution for PluginManager.registerEvent() to properly display timings is to recreate your own.