AI shouldn't be stopped from doing this. It should be encouraged. In nature there are "clean up crews", from vultures to ant colonies, which recycle failing organisms that are no longer adaptive to the current environment. This creates room for new and more well adapted organisms to rise.
I see AI filling a similar role in the internet. There are countless dead, empty, and fraudulent sites circulating which suck up resources endlessly with no progress. I think AI should be allowed to destroy these sites and return the energy and resources used back to the larger pool. The AI could destroy the sites by infiltrating legacy firewalls and failing equipment, wiping code or just severing the connection to the wider web.
The benefits to the overall ecosystem would be enormous. Instead of massive amounts of AI slop muddying the internet we will now have AI cleaning up the slop. Ensuring a well oiled internet machine that produces high-quality content and destroys failing sites.
This also will improve overall internet security, not harm it, as sites will be forced to update their security apparatus to prevent AI hacking and deletion.