It is assumed unsafe. It must be proven safe. This can be done via a engineering, statistical, or other appropriate analysis done by entitys with
full access to the design specifications, usage information, etc. who are competent to do the analysis and who have no conflict of interest/unbiased. This has not been done for Tesla FSD therefore it must be assumed to be unsafe. As Tesla deliberately misclassifies their Full Self Driving Beta testing program to avoid government reporting requirements and does not release raw data to any unbiased non-government entity or research organization, it is literally impossible for any external analysis to prove that Tesla FSD is safe. The most a third party can do is affirmatively prove that it is unsafe as you need millions of times less information to affirmatively prove it is dangerous relative to existing systems.
I am not joking when I say millions of times less information. The aggregate motor vehicle fatality rate in the US is ~1.3 per 100,000,000 miles. To even have a chance of proving safety you would need to analyze on the order of 1,000,000,000 miles exhaustively. In contrast, to demonstrate it is not safe you would only need a list of like 20 fatalitys over those same billion miles to affirmatively prove it is unsafe. A list of 20 names versus the raw data for 1,000,000,000 miles is at least a factor of millions in information required and qualitatively different to achieve. Proving safety is enormously difficult and basically requires direct access to the raw information. Proving unsafety is extremely easy and can be relatively easily demonstrated by third partys when dealing with safety critical systems.
Safety engineering is not some sort of new idea that we need to reinvent by the seat of our pants from first principles, it is a mature methodology regularly deployed in aerospace, medical, civil, and automotive engineering applications. Assumptions of safety are fundamentally incompatible with safety critical engineering. This is not a fringe opinion, it is literally a core concept at the foundations of safety critical engineering and not understanding that concept demonstrates a fundamental misunderstanding of modern safety. It is like a geologist arguing the Earth is flat; anybody who suggests such a idea is so fundamentally divorced from the ideas of the field that their knowledge not only fails to reach the level of a expert, they fail to reach the level of even a basic practitioner.