As you note, car owners are vastly less careful than certified plane owners and pilots, and yet the basically untrained car owners are 3-5x safer driving. As this thread was about enabling private flight vehicles for "everybody", it is clear that private flight vehicles are nowhere near safe enough for "everybody" if even the comparatively highly-trained certified plane owner is much less safe than a basically untrained car owner since private flight vehicles for "everybody" would undoubtedly be operated by basically untrained flying car owners making the danger even more pronounced than a mere 3-5x.
I EXACTLY stated: IN USA, aviation safety few times worse than in EU. But when you consider pure numbers, you should understand, that in EU totally different distribution of planes sizes and of airfield sizes. Sure, Frankfurt is safer than ground field somewhere in Austrian Alps, and number of small airfields in USA far exceed any other country.
You confusing typical humble car owner with certified plane owner.
Automobiles could for years don't see any care, even could be used without insurance, but still considered in statistics.
Planes of general aviation, are closer to city buses, which are under constant care and have very good support.
And yes, exist planes without rules, but this is difference, nobody care about non-certified automobile on private land, but you will lost pilot license if you'll get caught flying on non-certified plane, except very few special cases.
Also you should be careful, when compare statistics of US and EU, they have significant differences.