I'm the admin and owner of the feature service. Adding to a new Web Map. The table option is not available for the point layer in the service. The related table is (under tables, not layers). Hosted Feature Layers not created through Survey123 are fine. A hosted feature layer view of the same problematic layer has the table option.
Simply put, a feature service created with Survey123 doesn't give the option to open the attribute table from the layer in Map Viewer.
Looking like a defect...