The report makes precisely the opposite claim. It says small cars have a higher rate of fatal accidents. From the report:

"When broken out by size, small cars have the highest fatal accident rate while midsize and full-size cars are both below average. While modern small cars benefit from the latest engineering and safety tech, they still have a size and weight disadvantage in accidents with a larger vehicle."[0]

Perhaps you are right and weight is a critical factor, but then you'll need to explain why the heavy Model S was lower in their rankings than the Toyota Prius. It should also be noted that Tesla vehicles are generally lighter than most comparable EVs, and typically 0–10% heavier than comparable ICE cars.

I contend that this report is junk data. The authors haven't published the statistics (or methodology for collecting the statistics) used to normalise the raw NHTSA FARS data. Without it, its conclusions are as useless as you might suspect when looking at their top 23 list. (I wonder... if we knew what the 24th car was, would we know more about the motivations of the authors?)

That the only automaker name in the headlines stemming from this report is Tesla is proof that there's no intellectual integrity associated with its dissemination — it's just vibe, and an opportunity for people to push their pet explanations, even when the report itself contradicts them. Or when the pet explanation doesn't make sense of literally any data point.

[0] https://www.iseecars.com/most-dangerous-cars-study#v=2024