I thought you were a car guy? I can tell 99% of the cars (make and model) with a quick glance.
LOL
You asked, so here's the long boring details of how my mind works when driving...
I rarely focus in that much detail on any static stuff off the road when I'm out driving. I'll focus on a car on the side just enough to determine if it's a cop or if it's about to move onto the roadway or is otherwise presents a threat. Then, unless there's some reason not to do so, my focus moves past that car. I would have to be in heavy and very slow moving traffic to actually waste time even thinking about car brand or whatever.
Certain cars on the road itself
will jump out to me, be instantly recognizable because I have an interest in them. Examples are high-end sports cars, modified performance cars, unmarked patrol cars, etc. But I couldn't care less about ordinary cars like EVs or sedans or SUVs and so forth. I give them virtually no thought and wouldn't time identifying the brand/model/whatever. And no matter what the car is, any time focusing individually on an individual car will be sub-second most of the time.
Mostly, especially when driving on the highway, I don't focus on any one thing and instead see and sense patterns. When there's either a dangerous pattern or some kind of an outlier, then that will draw my attention just long enough to determine if there's a potential threat and I need to react in some way.
A really simple example is when coming up from behind in the left lane, there are common "behavioral" patterns for cars approaching slower moving cars in the right lane(s). Often there's a cue to ease up and possibly slow because a car approaching slower moving traffic is thinking about switching lanes to pass, creating potential danger either by itself or by cascade effect. There are dozens of these patterns and I'm constantly scanning ahead for them.
Another common pattern is state police who exhibit very recognizable driving patterns that help identify unmarked cars.
On country roads, it's more about scanning for slight movement (deer), or anticipating and adjusting to risk ahead (blind elevation changes, blind curves, stuff like that).
