Besides the heterogeneous nature of being an "Indian", the wobble is just agreement.
The person who's wobbling their head is agreeing to what is being said. It's not a yes/no.
It's mostly a "Go ahead and say what you want, I'll do what I want to do after you're done".
I didn't grow up in India, so I can see it for what it is, but I am Indian, so the subtleties are visible to me.
And aptly, people who don't need to take any shit/be kind in that instance/appear submissive don't "wobble" their heads. Those people mostly reserve it for their elders (parents/elder relatives mostly).
Perhaps similar to the verbal “uh-huh” or “sure” that Americans - at least in the Midwest - would use to affirm attention to what a speaker is saying but without actually stating agreement.
“Eeeh” or “meh” would indeed signal mild disagreement, but it’s stronger.
I’d say there is a slight inflection to the “uh-huh”/“sure” (almost a low-tone questinging iflextion?) to indicate less-than-full-throated-agreement, but that’s difficult to convey in writing.
which are you saying is "more negative" eeeh or uh-huh? The way I hear it, eeeh is much more rude or insulting, but also has more levity. Uh-huh is a mild eye roll sarcasm meant as an insult, more to the side of someones back. Eeeehhh, is "pretty sure you are wrong" to their face.
In my experience it can also be an ACK signal. Not a yes or no just a periodic acknowledgement that they are following what you are saying as you say it.
The person who's wobbling their head is agreeing to what is being said. It's not a yes/no.
It's mostly a "Go ahead and say what you want, I'll do what I want to do after you're done".
I didn't grow up in India, so I can see it for what it is, but I am Indian, so the subtleties are visible to me.
And aptly, people who don't need to take any shit/be kind in that instance/appear submissive don't "wobble" their heads. Those people mostly reserve it for their elders (parents/elder relatives mostly).
Take all of this with a huge grain of salt.