It's not a matter of knowing what type of vehicle it is, it is a matter of properly being able to estimate the speed and distance. Cars can travel all sorts of speeds and still be a "car". Miss judge the actual speed or distance when you pull out and a problem exists.

I bring up motorcycles because they get pulled out on all the time. Like you said I think most drivers don't want to hit anyone, I know I don't, but I can tell you first hand there have been times where I've been surprised how quickly bikes have closed on me. I'm not sure if that is because I misjudged the speed or the distance, just know it seems different with bikes, my guess because they are smaller.