i also once read that Gregorian chants were based in temple jewish music. there is also an interview i once saw in which yechiel nahari explains that the arabic music he learned in egypt and syria were brought there from the jews of the first temple. they both cannot be true and considering the total lack of any real evidence for either i dont believe either one to be true.
i want to be clear. music can certainly be broken down into genres. rap sounds nothing like country which sounds nothing like tarab which sounds nothing like opera. sometimes genres can touch – country/folk, rock/punk etc. or borrow from one another (r&b/jazz). jewish is not a genre of music. all jewish music we listen to today fall into other genres or are very closely related. mordechai ben david and avraham fried fit nicely into russian genres of music plus loud horns; the boys choirs are pop and electric with loud horns; schwecky is rock and pop with loud horns; dveikus is folk; lipa is rock, rap, pop and electric (and some annoying horns). there is beautiful music in all genres but the songs called jewish music are usually just really, really (extremely) poor exhibits of their particular genres.
chazzanus and niggunim usually are exact copies of songs within european genres the way the sfardishe chazzanus is usually an exact copy of allepo, baghdad and egypt music genre songs. helfgot is a classic opera singer and habusha is a classical tarab singer. there is nothing jewish about their music.