Whether it’s relevant or not, don’t know, but all the parking spaces I map, helped by Gridify in JOSM, have the parking_space=* as supplemental tag e.g. disabled, normal, bus, hgv, delivery. That said, no reason but for some renderers the spaces do not all show up, almost random fall out, but in Carto standard I’m seeing 100% for normal, family, disabled, delivery.
