Hello olivercat,
While I agree with you that this segment of CA 168 (as well as all other segments of Highway 168 between here and Kaiser Pass Road) should be marked as Highway=primary (because of its regional importance in servicing minor population centers see: https://wiki.openstreetmap.org/wiki/United_States/2021_Highway_Classification_Guidance#Primary), there has been much discussion over this question. Please make a FIXME tag on this topic to bring this question to other mappers if you agree.