Learning to fly is hard, period. There are no shortcuts. It takes all your concentration. Your mental bucket fills up as you struggle to maneuver in 3 dimensions. There’s a whole internal conversation you carry on with yourself as you do the stick and throttle thing.
Now add radio work to the mix. Mentally prepping for, and making a radio call requires you to stop the internal debate you are having about how much pitch change it takes to keep level flight during a turn. Somehow, you have to quiet one part of your brain, so the part that makes the radio call can energize. It doesn’t come naturally.
Talking and flying is a learned behavior. It takes as much practice to get your radio calls right as it does to get your landings right. Like landings, maintaining proficiency on the radios takes repetition. When the Aircraft Radio Simulator goes fully operational online, you’ll be able to learn and practice radio calls to proficiency.