Should it be possible to add https://www.arcgis.com/home/item.html?id=de8bb22f53914e9b906345e7e9dd2a38 to a new map on arcgis.com using the Map Viewer Beta as a basemap?
I went to Add layer, searched for the item ID (de8bb22f53914e9b906345e7e9dd2a38), clicked on the title of the result ("World Imagery (Wayback 2019-06-05) Metadata"), and clicked "Use as basemap".
Then, the map went blank and the F12 browser console said that requests for URLs like "https://metadata.maptiles.arcgis.com/arcgis/rest/services/World_Imagery_Metadata_2019_r07/MapServer/... resulted in a 404.
I also tried item ID 2de04974bcf148838142e57d74aaf379 and got the same error.
The wayback imagery is shared in WMTS format which is not supported in the new map viewer - OGC—ArcGIS Online Help | Documentation.
"OGC Web Map Tile Service (WMTS) is a set of cached image tiles that follows the WMTS specification of OGC.
You can do the following with OGC WMTS layers in ArcGIS Online:
Add them to maps in Map Viewer Classic. See an example.
Add them to scenes in Scene Viewer.
Add them as items in your organization."
That's strange; https://developers.arcgis.com/javascript/latest/api-reference/esri-layers-WMTSLayer.html says that WMTS layers are supported in the 4.* JS API.
Is the new map viewer using a version of the JS API that predates 4.4?