“Cowboys” are few in the aviation community. Most incidents come from those who are not current with what is going on and stumble through restricted airspace and fail to read NOTAMS, “notices to airmen”.
Mail slot for flight plans? Who picks up the mail? I just call my local Flight Service Station and file with them.
I flew with a guy out of MacArthur Field on Long Island, which had a tower. He more or less completely ignored ATC. He jumped the line to land, and we were passed by a 727 on our port side about half a mile over at the same altitude. My pilot friend was asked to leave MacArthur and he went to smaller airport, where there was a mail slot for flight plans. Mostly only useful to determine where to expect the wreckage to wash up once your wife hadn’t heard from you in a couple of days.
Foxnews Boston interviewed local pilots at Norwood, another closed ATC tower, and they seemed completely unconcerned. The only one who seemed concerned was the ATC controller.