If I want to remove a database (db) connection from my project I locate the db in Catalog, right-click on it then choose 'remove'. This makes sense, the db is removed from my project and does not get deleted
If I want to remove a linked web map from my project I locate the web map in Catalog, right-click on it then choose 'delete'.The map is removed from my project and does not get deleted from portal. If I locate the same map in portal right-click on it and select 'delete' it will delete the item.
If i choose delete for a normal project map in Catalog it will be deleted - as expected.
I think the language (including the tool-tip) used when removing a web map from a project's Catalog should be changed from delete to remove.