Yeah, but there is no way Carto would work whatever proposed solution for tagging was used, right?
It has limited max zoom level, and whenever two amenities are close to each other it will always pick only one to render, and not always in deterministic fashion. Luckily, as the saying goes, OSM is not just a map (especially not just Carto!)
Perhaps vector tiles will help there for “default OSM map visualization”; but in the meantime many other data consumers (like e.g. OsmAnd) can easily search for and display recycling bins and/or waste baskets when they are mapped as separate-but-closeby nodes.