>>130059361
Your premise is a bit off because classical isn't inherently more "harmonically compelling" (subjective) than jazz, but you're definitely noticing a difference in how harmony is used.
I'm going to horrifically generalize here but in classical (especially the common practice period), the harmony is very teleological. Chords have functions and they point somewhere, tension resolves, and everything feeds into some kind of long-range structure. It's also more about voice leading, meaning the harmony grows out of relatively independent lines rather than just stacking sonorities. By contrast, a lot of jazz leans more toward color instead of function and more toward vertical sonority, where chords can exist more for themselves, so even if it's dense or complex, it can feel less directional.
But you're also forgetting that a lot of classical music is coloristic and vertical too; composers like Wagner, Debussy, Scriabin, and Messiaen can get very static and "directionless" (not in a bad way). So it's less a strict classical vs. jazz divide and more about a broader shift toward more vertical, less teleological thinking in 20th century music in general.
Also, it's kind of ironic you posted an image of Bruckner, since he's often described as very vertical, spacious and block-like rather than linearly developmental, and people who dislike him usually call him meandering.

>>130059361
it's well structured unlike jazz, this has been discussed to death

>>130059361
What I thought of was the amount of instruments used. Sure there are smaller scale works in classical and big band in jazz, but generally when I think of "classical" I think of a 100+ person orchestra playing a symphony and thinking of "jazz" makes me think of 3-5 people playing bebop. The huge variety and amount of instruments probably enables a lot more harmonic exploration in a given piece.

>>130060539
>he hasn't heard of chamber music

>i'm white