Bit of a non-story really.
(a) Nobody living ever heard Buddy Bolden, and he never recorded. Claims he is the inventor of jazz are unproven and controversial. The article itself notes that his music was closer to ragtime than jazz, which seems to be the general consensus from oral histories of those who did hear him. Mental illness may well have been "at the root" of Bolden's music, but it's a bold claim to then generalise it's "at the root" of jazz as a genre.
(b) Many great artists, in all fields, have suffered from mental instability, and the connections between, for example, schizophrenia and artistic production are well established in painting, writing and music. "Bolden was schizophrenic shock" is hardly a story. Bud Powell, Thelonious Monk, Charles Mingus, Charlie Parker, and many other jazz musicians suffered periods of mental illness, sometimes protracted. They are great musicians, for sure, but many other equally great composers and improvisers don't appear to have had any mental problems at all, so it's a bit of a stretch to claim some intrinsic connection between schizophrenia and improvisation. On the contrary, Monk's and Parker's worst periods of illness coincided with periods where they made either their least interesting music (in the case of Parker), or gave up playing altogether (in the case of Monk).
(c) If anyone has a strong claim to have placed the improvising soloist at the heart of jazz, it's Louis Armstrong, a claim that has the benefit of recorded evidence. For sure, plenty of New Orleans and Chicago musicians improvised before Armstrong, but his early recordings were more influential in the long term than anybody else. (Miles: "There's nothing you can play on the horn that Louis hasn't already played".) There's no eveidence that Louis suffered from schizophrenia.
(d) The early history of jazz is fascinating, but frustratingly foggy. No one individual can be identified as the person driving the evolution from ragtime to what became "jazz", and all such claims, whether they be for Bolden or Jelly Roll Morton or whoever else, are unproven and overstated.
-- Ian