I don't really see the sense for breaking this down by nation, beyond having nation-scale car statistics to compare against... I mean, the Boeing max fuckup could well be regarded as "made in the US" no?

Redundancy plays a part, but it is not a major one. Major differences include the amount of scrutiny and government supervision in terms of inspections, certifications, regulations, maintenance, traceability, medical checks etc. that commercial aviation requires and the difference in technology and support between a modern commercial airliner and the average general aviation plane.

Engines are a big one. But the reasons are innumerable. Commercial aviation is always scheduled, so you have a very definite takeoff time, location, and destination. This cuts down the variables encountered along the way greatly and allows for precise route planning taking weather and traffic into account at all times. Commercial flights are also 100% IFR even in perfect weather, which means their every maneuver is coordinated with ATC. ATP pilots are also literally 100x the experience of your average GA pilot with a couple hundred hours. Not only that but they are in regular practice, not just someone hopping in the left seat for potentially the first time in years. They're also held to a much higher medical clearance level by the FAA, so you have far fewer medical incidents inflight. GA also includes training flights too, which contribute a significant amount to the accident numbers.

Equipment used is part of it, but smaller than you’d imagine.

Well maintained single engine aircraft (in the certified category) are generally reliable. The majority of incidents in these planes come down to avoidable pilot error. Looking at the forces behind pilots making mistakes will provide a lot of insight. General aviation is not forgiving to mistakes and tired, under-trained, overconfident or briefly otherwise human behavior can (and does routinely) cause issues. These factors are more carefully compensated for on the commercial side.

Of course, the counter argument here is the missing safety features that should exist to compensate for mistakes.

The engines aren't the big difference. It's the operating procedures in commercial aviation that are much different. If I step into a single engine Cessna in my private time, I'm allowed to fly with almost no equipment, very little reserve fuel, no plan for an alternate airport, in shitty weather all by myself.

Now if I step into a plane with passengers (even if it's the same small Cessna), suddenly I'm no longer allowed to fly single pilot IFR operations without autopilot, need much higher fuel reserves, need to plan an alternate, check weather requirements and have done a 6-monthly checkflight and training. And for most airplanes I would also need a co-pilot, so there are two people monitoring everything.

Most small airplane crashes are not due to engine or equipment failure, mostly it's pilot error, and that's where all the extra procedures in commercial aviation really help.

One more reason, not mentioned above, is ability to fly in weather. CA airplanes have proper de-icing for wings, are big, and fly above the clouds.

A lot of GA -- certainly anything under around $200k -- is a fair-weather activity. Planes can't really fly in the winter -- ice builds up on wings. Strong winds throw small airplanes around. There isn't instrumentation to land with limited visibility from fog, severe snow, or severe rain. Etc.

Weather can change unpredictably. If you've flown for a weekend getaway Friday, the weather turns over the weekend, and you have an important business meeting Monday morning, do you risk flying back? Do you miss your meetings? Do you leave your airplane there and fly back commercial, with thousands of dollars in hanger+rental fees and days of hassle to get your airplane back?

It's a value call. Different people have different risk tolerances based on personality, life situation, and culture.

A lot of this applies to cars too actually -- if everyone drove conservatively, they'd be pretty safe. At least where I live, virtually everyone speeds. People cut other cars off. Etc.