The base is original from the producer (chords and melodies), but is complemented with elements that complement the song that come from samplepacks, usually, vocal chops, guitars, wobbles sections, glitch effects. It is the standard in which most of producers work, in a project you will find MIDI files made by the producer, but also melodic loops.
Main sounds are made on Serum and Korg M1, supporting synths are created from processed one-shots and tonal sfx.
Sample pack Sample Magic - Flipped Funk
Loop name FF_horns_resampled_vinyl_fanfare_Amin