To quote the wiki itself:

https://wiki.openstreetmap.org/wiki/Tag:highway%3Dpedestrian

> Vehicle traffic is generally restricted [...]

Clearly, that's not the case for Ki Lung Street.

For the many routers that rely on OSM data, them skipping `=pedestrian` for motor vehicles is expected behavior. Then, having `=pedestrian` simply misleads them to believe Ki Lung Street is inaccessible to cars.