Cherrybim, can you site a source for that? Litvishe davening has always been with a minimum of musical accompaniment. My Rosh Hayeshiva ZT”L loved listening to chazzanus tapes, but didn’t want it uring davening, as he felt it detracts from davening. In the olden dayd, the choir leader would have his back to the aron and the choir would wear those scarf tallises. then they would all go out and be mechalel Shabbos together. The chazzan like Cantor Rosenblatt who wasn’t mechallel Shabbos was a rarity. This fake Judaism fools nobody. How uplifting can it be if they can go out afterward and be mechalel Shabbos? (I also find myself wondering how someone such as yourself, who sincerely believes chazal made up the megilla as part of a petty vendetta against the Hasmonean kings, can speak of singing and being uplifted by the words of those selfsame chazal.)
One of the big changes of young Israel was they made davening participatory and made it more appealing to the masses. Chassidish davening is like that too. This is music for the “amcha”. I’m not a big fan of this either, actually. I’m davening in a shteeble, everyone is singing and clapping, and suddenly they stop the singing and yell “oomine!” That’s kaddish?
Master cantor chazzanus is a type of performance art. I’ll take kavanah over performance art any day. Obviously, Rosh Hashanah and Yom Kippur’s “scarbova” chazzanus is on a different plane. Those are ancient melodies going back hundreds of years, with a power to move that matches nothing else.