I also control my LG TV from R2 via my HA and I have no delay when I push a button multiple times. Cannot tell for Apple TV as I control that via the native UC integration.
For instance, when I hold the Channel-Up button pushed for some seconds my LG TV runs fluidly and fast through the channels without any delays or stops.
Here is a screenshot of my HA “Channel-Up” script for the LG TV:
