You have defined one of the aspects of a non-pilot trying to land any airplane.
When I was a full-time instructor, 30 years ago, I had a senior 747 captain come into the FBO where I instructed, wanting to get checked out in an Arrow so he could take his family for a ride. I was fairly new at instructing and thought if this guy can fly 747s, then he surly can fly an Arrow. We did the ground work and went up for a flight. All was well until we were on short final. We were getting slow and just as I pointed to the airspeed and said, "we're slow" he started his flare, about 100 feet too high, and at the same time pulled the power to idle. In a piston engine, when you pull the power to idle, it goes to zero thrust immediately. The airspeed got way slow and the stall horn started chirping at us. I went to full power and pushed the nose down, this to save us from stalling and nose diving into the ground. I had to literally jerk the yoke back to try to arrest the fast descent rate. We hit the ground on the rear wheels, nose high, with a pretty high descent rate and slow. Of course we bounced. To make it worse, he never let go of the controls, so I was working against him. This all happened in about 5 seconds. It scared both of us. All because he wasn't familiar with a Piper Arrow. If I hadn't been sitting beside him, I am 100% certain he would have crashed.
We taxied to the hanger in silence. We got out and he walked to the office, paid, and I never saw him again. He didn't log the time or get my signature in his log book. He knew he had no business in small airplanes, unless he was going to get some serious instruction time and he wasn't interested.
The hard landing sheared a bolt in the landing gear. Which wasn't found until the 100 hour inspection about a week later.
I never again assumed anything about any pilot I flew with.