One day you start getting a bunch of people come in to mess with the place. You can identify them and their organization, then promptly remove them. If they continue, there are legal ramifications.
On the web, these people can be robots that look just like real people until you spend a while studying their behavior. Worse if they’re real people being paid for sabotage.
In the real world, you arrest them and find the source. Online they can remain anonymous and protected. What recourse do we have beyond splitting the web into a “verified ID” web, and a pseudonymous analog? We can’t keep treating potential computer engagement the same as human forever. As AI agents inevitably get cheaper and harder to detect, what choice will we have?