Separate MIDI Region by Note Pitch

Separates the MIDI region into multiple regions, each with only one note pitch. Each note pitch gets a separate track. Remarkably handy for drum parts.

Demix MIDI regions in the Logic Pro Tracks area — Apple Support

This feature is especially useful for separating drum parts that have been recorded into Logic Pro from a drum machine where all notes are on the same MIDI channel. Each note region can then be assigned to another channel strip, or perhaps some can be deleted, to thin out the original drum pattern.