What steps are needed to communicate with ATC on an A320?
You need to even realize that you have to push a button to talk. Not everyone grew up with ham radio, CB radio, or walkie-talkies, especially nowadays where everybody has a mobile phone.
You need to find the PTT button.
You need to select where you want your headset to be routed: you can talk to your co-pilot, you can talk to ground crew, you can talk to the cabin crew, or you can talk to you radios.
Note the plural above: the plane has multiple radios. You need to select the right one.
You need to know the frequency of the ATC entity you want to talk to.
You need to tune the radio (the right radio) to that frequency.
Every radio has an active frequency and a standby frequency. You need to make sure that you change the right one. (Either change the active one, or if you change the standby one, you need to make that one active.)
You need to realize that radio is a shared medium, and that only one person can talk at any one time, and that you need to wait for a break.
Depending on how busy the frequency is, you might not even recognize where the pauses are, or you might not be able to squeeze yourself in because you are not used to talking that fast and efficient.


I consider myself technically adept, and I used to do a little bit of CB radioing in my youth, but I'm not sure if I could figure all that out in 20 minutes.