This is a great point.
Let’s think about the impact of a freshly minted new user who lands on the ‘Identifier’ page. However, unfortunately this particular new user has no genuine interest in naturalism and only wants to entertain themselves with vandalism. (This is an extreme example but I think it helps illustrate the point)
If the vandal was able to assign “course” taxa to multiple observations at once (let’s say, they ID a large group of frogs and plants as “Avian”), their vandalism won’t affect the level of scrutiny that observation gets on the site. The observation will remain as “Needs ID” until it meets the criteria for “research grade”, and eventually the vandal’s ID will be labelled as “Maverick”.
However, the vandalism possible if an individual inappropriately uses the “Agree” button to confirm large numbers of observations they have no idea about, has far more potential for harm on the site. Because anyone can “Agree” with species level IDs even if they have no idea, there is a significant risk that large amounts of observations on the site will change from “Needs ID” to “Research grade”. As a consequence, this would lead to these observations being filtered out of the workflow of legitimate Identifiers, and thereby actually allowing rampant “Agree” vandalism to prevail in the database and bypass scrutiny.
In summary, I’m arguing that a bulk ID (+ reversal) tool, for course taxa only, is less risk than the existing “Agree” button, which can be used to provide a false species-level ID