I’m talking about music that is similar to this. There’s a melody and a tone, and the transition between notes isn’t random or jarring, so it’s not anathema to Western ears. Nor is it, for lack of a better choice of words, random noise that could be categorized as music, such as atonal opera. But there is no call-and-response which, by my estimation, is pretty foundational to Western music.
So what would you call it?
Ambient?
Syncopation?
Or rather I should say non-syncopation. Syncopation is rhythmic style that is not common in Western music (but common in African influenced styles), that I think may be what the OP is talking about (I am way out of my depth here though 
)
Drone music. The classic Western example of this style are the bagpipes.
As QQ said, ambient. Or trance music, perhaps?
I’m not sure that call-and-response is all that foundational though?
It’s a very common pattern, but only one of many. Most often seen in more improvisational contexts like jazz and blues where two or more soloists are playing off each other?
In the classical tradition I would say an equally common pattern is development of a theme. Where an initial seed becomes increasingly elaborated as the piece progresses. There’s no hard and fast distinction between the two, though…
I want to thank you for introducing me to “atonal opera.” Now I can give my Yoko Ono records a rest.
I agree with other posts which say your example is “ambient music.”
However, with all due respect, I agree with xtenkfarpi & Q.Q.Switcheroo that you are confused about the definition of Call & Response.
Call & Response is NOT “foundational to Western music.” While it is not too exotic, it is far from common. It is a specific musical device which incorporates repetition, imitation, and alternation.
To demonstrate my point, I will give three examples of Call & Response.
•I Got My Mojo Workin’ (Muddy Waters
etc)
Muddy: I Got My Mojo Workin’
Band and/or audience: I Got My Mojo Workin’
Muddy: I Got My Mojo Workin’
Band and/or audience: I Got My Mojo Workin’
Muddy: I Got My Mojo Workin’
Band and/or audience: I Got My Mojo Workin’
Muddy: I Got My Mojo Workin’
Band and/or audience: I Got My Mojo Workin’
Muddy: I Got My Mojo Workin’ but it just don’t work on you
•School Days by Chuck Berry
Sings: Up in the morning and off to school
(Guitar solo echoing same melody)
Sings: The teacher is teaching the golden rule
(Guitar solo echoing same melody)
•A Certain Girl
(written by Allen Toussaint; originally recorded by Ernie K-Doe; also recorded by Warren Zevon, Yardbirds, etc)
Leader: There’s a certain girl I’ve been in love with a long
Band: What’s her name?
Leader: I can’t tell you
Band (disappointed): Aww
OK, I’m definitely confused on Call & Response. My bad.
Glad I could clear that up for you. I understood what you were trying to say.
Yeah, this.
To me, the music in the YouTube clip in the OP is even “dronier” than bagpipe music.
ETA: Just for fun I’ll mention that banjos and sitars have a drone also.
It’s a bit monotonous.
I gave up after about 8 hours.
I,'d go with “ambient” for the overall style and mood of the piece, but “ostinato” for the technique.
Or maybe “minimalist”. Or is it AI-generated?
(slightly ot maybe): Once, when I was the world’s worst truck driver, I was parked in a lot and started hearing really faint flute music coming from somewhere. It was like a flute, and the music was totally structure free, but not disagreeable. After a while I climbed out to find the source. It was loudest coming from the rear of the rig parked next to mine. I found out it was his mangled doors that were acting like a big harmonica in the wind.
What were they trying to say? Verse/chorus/verse? I am confused, as I came in to the thread knowing what call & response is.
I don’t know how to describe it. Basically, almost all Western music, as far as I can glean, goes like this:
Series of notes I series of similar notes that kind of “answers” the first series of notes.
Take Beethoven’s 5th:
Four big notes I Four big slightly-different notes
Twelve notes I Twelve slightly different notes
Six notes I Six slightly different notes
Or take “Basket Case” by Green Day
Do you have the time I to listen to me whine I About nothing and everything all at once
I am one of those I melodramatic fools I Neurotic to the bone no doubt about it
Ah, gotcha. I never really noticed that about music! (I am absolutely terrible at music theory)
Is “motif” the word you’re looking for?
Fuck if I know. What I don’t know about music could fill several libraries.
Yes, that was my understanding. Or “structured” as son_of_a_rich wrote.