Thing - gash is the word I'd use. Most have no air experience at all and therefore do not appreciate workloads.
It's the same at the other end you know! As someone who is very familiar with both ends of the radio, I can sympathise for both sides.
Just because you don't hear anything on frequency it doesn't mean the controller isn't maxed out too. They may have landlines to other agencies ringing, be trying to prenote another aircraft, hand over another aircraft or be working multiple frequencies at once. Asking you to do two things at once to save them time on frequency is a necessity. Remember you're not the only one they're talking to and while they are talking to you, they can't talk to anyone else, so someone somewhere is going to have to multitask!
I am a newly solo pilot so I do understand workloads at the 'sharp end' too. ATC aren't all dragons who are trying to make your life difficult.
While on the ground listen to all calls but when in the air only listen to what is meant for you --- this will reduce the mental workload while flying.
I would disagree, maintaining a listening watch will give a much better understanding of what is going on around you. You don't have to listen to every word, but knowing where another aircraft is because you have heard it may help you out if you haven't seen it.
Capacity comes with experience, you'll get it in time.