I really would like to see the quotes come back at the very least as a toggle. Hearing the quotes really aided in the narrative/world building for that match. Most people play a small set of champions with any regularity. We don't often get to hear the voice overs of the other champions and it is often a treat. Hearing the voice overs of "Tonight We Hunt!" followed by "Feel the Thorns Embrace" gives me a sense of where the other team comes from. It anchors the match with a sense of place and not just it being a contrived something from nothing.
To put it concisely, League with the broadcasted champion select quotes is much closer in immersion to the "A New Dawn" cinematic than a League without them! If reaching that level of immersion is your goal -- then these broadcasted quotes need to come back.