In the days when prop swinging was common I think pilots were much more aware of the inherent dangers - in fact, you had to be "checked out" on prop swinging - this would not be a "one off" but you might do it several times to the satisfaction of the instructor teaching you before you went "solo".
These days, more often than not, you just press the starter button.
I have discovered that most pilots these days don't even understand what "thumbs up" or "thumbs down" between cockpit and outside means.
There is nothing wrong with "running changes" so long as they have been properly briefed and are well supervised. If not it's just far safer to shutdown rather than take any risks.
At the end of the day, it's the pilots who are responsible for their "passengers" safety.