kids are not stupid they know it's lack of thinking not disrespect. Most people when shmoozeing if you'll politely remind them they would stop.
P.s. You would make a good speaker!
It depends who but a lot has to do with the parent. If a parent doesn't talk in shull, the child will generally be OK about being reminded to be quiet.
In my shull, you have guys dressing like chasidish bochurim, who manage to to hold conversations while simultaneously davening, they will sometimes break to daven with impressive shows of kavana.. Or you see guys have conversations while learning dvar malchus.
It really is one big reason of otd as we discussed in the swingers thread. It's just crum, Judaism as an empty shell.
It makes a mockery of the mikdash me-at, of tefillah, of god.
It pisses me off how the uber from litteraly spit at god, this is a epidemic in chabad (and pick up garbage tissues from the floor dammit ) yet I daven at modox shulls where women don't cover their hair, the mechitza is see through over 3 feet, and the women wear pants etc etc etc all and god forbid you would not catch these people talking in shull.
It's really why I struggle to much with orthodoxy and finding meaning, it's like Judaism is just a ritual, they would not be caught dead eating machine matza but meh talking during kaddish? Who gives a hoot