Virus do abuse non executables like js, vbs, or whatever script file. Antivirus can't really know if it is the case without open it.
Is it really just that Windows users download and run random junk? It's been so long that I've seen a virus of any kind anywhere at all that I genuinely have no clue how people become infected with them or indeed whether it still really happens at all.
It certainly feels to me that the era of random toolbars and clearly visible desktop malware is over, but at the same time I live in a different bubble than in the past.
I'm a bit late to the conversation, but can confirm that yes, people do still get infected.
We almost always turn something up while doing virus scans at the repair shop I work at, and we mostly use off the shelf products, along with a couple other tricks.