Due to I am a bit into "shamanism", at least I am on my way to study it, and lets see how far I come (so I am NO shaman), to me Kava was always more than just a "non-psychedelic" from the beginning.
Especially 1-2 days after consuming (depending on mind state, cultivar and dose), I have very lucid dream worlds, and other experiences. But this forum is the wrong place to discuss it or to go more into details.
Also I had experiences while consuming kava directly (not the 1-2 days after). It isn't the same as strong psychedelics, but to me it has psychedelic qualities - no question.
I had HPPD once after a Peru Trip many years ago, which went away after 2 years +/- . But the effect of kava differs very much to this HPPD I had, it is something completely different.
Seems some people are just a bit "broken up/open" and react different to things like Kava. Or some people have a very sensitive body and brain chemistry. Leaky blood brain barrier, btw, seems to be existing, too. Many Drs aren't aware of that, sadly. Some don't even believe in leaky gut.
Remembering a youtube video of a tribe on an island who used kava to connect to their ancestors.