This is the (pretty crappy) way osm maps lanes. "lanes" counts for lanes where a 2-tracked vehicles (cars, buses, ...).
For me it looks correct now, see:
https://wiki.openstreetmap.org/wiki/Lanes

"""
Pay attention to the value of the lanes=* key. The number of lanes is referred to the lanes available to the traffic using the main highway=* key, in this example and also by definition of lanes=* key motorized traffic, what excludes bicycle lanes.
"""