Right! They even have road-paving machines that rip up the asphalt; add a bit more tar to replace the tar that seeped away; heat up the mixture and tumble it; lay it back down; and steamroll over it; all in one pass, all in a closed system with no dust escaping. (Ref: https://youtu.be/XKFaC5RYbEM)

Plus, since asphalt’s petroleum-tar binder is liquified during the working process, it would actually act as a solvent perfect for dissolving (certain) microplastics into. The microplastics wouldn’t merely be in mechanical mixture with the asphalt; they wouldn’t exist as distinct entities any more! They’d revert to being a petroleum fraction, in complex with the heavier petroleum fractions of the tar.