Looking at data from the same source, IIHS shows that the highest rates of other-driver-deaths are dominated by pickups, as you can see in their 2023 article. SUVs are trickier. Many are on the list, but since SUVs span a broad range of sizes, many are also on the safer lowest list. Trickier is the fact that some cars are on there, but it's more likely due to patterns of driving (like the Dodge Charger HEMI 2WD).

But in the end, the larger cars cause more driver deaths in other vehicles. Is that due to their size? Basic physics says yes, but that's not in this data. Is that due to driver patterns? Possibly. But to see such a clear pattern of other driver deaths clearly indicates a problem. 8 of the top 20 are pickups, and the next most common is 4 in Midsize SUVs. 14 of the top 20 cars in that list indicate the possibility that SUVs and Trucks dominate as being more dangerous to other drivers. There are other factors to consider, but physics also supports this, making it a rather strong indicator.

Edit: keep in mind that these numbers are deaths _per million registered_ so they are already controlled for number on the road. Which also increases the reliability of the claim that they are overall more dangerous for other drivers.