Shell Management.You quote a few examples, which taken amongst the hundreds of thousands of uneventful flights every day, is statistically insignificant.
What is significant is the consistent efforts of many Airline Management fellows, especially seat-warming administrators and 'Bean-Counters' to denigrate the Captains' authority for commercial reasons.
These people have no idea of the proper way to run an Airline Operation; they think that anyone who can play with a desktop computer can exercise command on a heavy jet.
Until the Pilots' Associations stand up to this tyranny, it can only get worse.
In a completely unrelated incident, a friend of mine was asaulted last week. He is 65 and his aggressor was 40 or so. The aggressor got to the police first - huge drama.
In the above case, the Captain should have gone back to the cockpit, locked the door, and called security on the radio. He would then have had the initiative, rather than the Ground Staff Person who seems to have a problem with the perceived size of his appendage.
The alternative is anarchy!