OSM editing is usually "holistic" - you work on many aspects of the map
in an area. If the map has many edits by different people in an area
then I can reasonably assume that it has a certain minimum quality
because these people are on the ground fixing things.
"holistic" editing is not the only sort. The community is more diverse than that.
You'll find mappers seeking out one feature (e.g. dog walk parks).
Mappers doing wiki or tag gardening (like the original poster).
Mappers working to consolidate tagging, and mappers working to split apart
tagging and make it explicit.
And those focused on data imports.
Quality on the ground is probably better measured by views, both among mobile
apps like OsmAnd, and the tile servers. Who cares enough about the map in certain