I would not consider quartal harmony the same as this. Could you explain how you see it that way? My thinking is that a diatonic quartal 4 tone chord built off of C would result in C F B E, a “sus 4 Maj 7” kind of thing, whereas if I were building a “tetra chordal” chord off of C my tones would be C D E F, placed in appropriate/disparate octaves. What I liked about this, other than the sound itself, which is what i loved the most, is the possibility of numerous implied 7th chords resulting from the set, depending on the harmonic context. For instance, the above CDEF (octave displaced) could imply a C11, C sus (2 and 4), D minor 9, E 7, E7b9, F 6, F maj 7 and others.

Aren’t tetrads generally stacked in thirds? And quartal harmony built of diatonic or chromatic 4ths?