For non-cached content, sure?

All you have to do is exhaust enough database fetching and rendering on the backend for non-cached content and even amazon goes down (ie. black friday downtime).

It would take an impressive amount of resources but who knows what blackhatters are selling these days.

You'd need to use logged in accounts to get uncached content, so wouldn't you be burning through a lot of accounts to do it? Seems like something you could only do once in awhile. Doesn't seem worth it for a simple quarantining of a sub.