is it really highway=primary? It leads to a small group of buildings.

Note that OSM road classification is not obligated to follow official road classification

For example in Poland both https://wiki.openstreetmap.org/wiki/File:Korzeniewo12.JPG (state in 2010) and https://wiki.openstreetmap.org/wiki/File:Miko%C5%82ow_-_DK81.JPG (state in 2006) depict road of the same official class. They were not tagged with the sam highway tag.

Similarly https://wiki.openstreetmap.org/wiki/File:Droga_wojew%C3%B3dzka_nr_219.jpg depict 55m long, unpaved road leading to closed railway station. It is still legally classified as in important road, but has no high highway value.