One of the more eye-opening experiences I've had over the decades was going for a jolly with an ATCer, in and and out of a capital city CTR, in his lighty. He was a friend of a friend and I wanted to hire his aircraft for a trip.
Amazing how flexible the system was for a call sign whose owner was known by the folks behind the Airservices mics. Simply amazing...
After that, I did a lot more submission of departure and inbound details by radio, and continue to do so, when that's convenient to me. I take the - perhaps naively quaint - view that a government organisation with "service" in its name and sends bills should give me the same level of service as one of its employees in the same operational circumstances.
"Some places won't even let you in as a matter of course if you haven't submitted a plan." Which just goes to show, and has become evident to me over the decades, that differences of outcome in like circumstances are sometimes the result of the personalities, pet peeves and local normalised deviations of those in the system.
Someone usually pipes up and says the people concerned could have been coordinating with other sectors or dealing with other aircraft with plan in the system or dealing with a bee-sting or heart attack, and that apparent different treatment in like circumstances is because the circumstances were actually different. Great: Let's hear what the differences actually were. I do not want to know what the Controller/s involved could have been doing; I want to know what they were actually doing, and why the clearance was actually unavailable. Two sentences.
The Mooney pilot in this tragedy did some stuff that I have never done and, touch wood, would hopefully not choose to do in the future. But, has already been pointed out, there's no explanation of the "why" the requested clearance into C was refused. That simply invites negative speculation about the ATC system and ATSB's motivations.
The failure to make the raw recordings of comms in ATSB reports is, in my view, inexecusable and, again, merely invites speculation about ATSB's motivations.
ATSB - like some in this thread - have no concern about throwing pilots under the bus. One wonders how the ANSP and regulator have reached operational perfection, when they are chronically dysfunctional organisations from a human resources management perspective.