As a very minimum it should go as intelligence against the driver.
I had a guy threaten to run me down, I took his reg and reported it, full statement. Police took it further and suggested I press for charges. They looked into it and interviewed the driver, but couldn’t take it further as it was my word vs his. They did say the incident had been logged as the ‘vehicle’ had had other ‘reports’ against it. Basically, if they get pulled for something more severe, these ‘reports’ will get taken into account.
If this guy is going to spit from his car, I’d suspect he may have previous.