Respectfully, I disagree. That does not even fit the definition on the SpamCop website.
While abuse reports are certainly unsolicited, they aren't bulk. And therefore they aren't spam. Further, why should the negligent administrators get a free pass from having to deal with the headaches caused by spammers they are permitting to operate? For every 1 email their spammers send, they should have to read at least 1 email themselves, preferably more, until the problem is dealt with.
Regarding reputation, if Amazon AWS, a gigantic hosting company, has been doing nothing about spam on it's network, then surely there must be a ton of spam coming from it's network, why aren't they blacklisted by now?
Sendgrid is another company I've noticed that is being /dev/nulled. They're a bulk email company, so it seems even more despicable that they should somehow not have to take responsibility for their actions. In the case of Sendgrid, the spam I've received from them has unsubscribe links but they do not function, which is a violation of the CAN-spam act and should be getting reported to them, but because of the /dev/null policy requires I send them a unique email every time which is a _huge_ inconvenience and probably ensures that they receive far fewer reports than the problems justify.
I understand SpamCop doesn't want to be seen as hostile or troublesome, but where is the harm in shaking things up a little? spam is a problem because of negligent administrators, more than any other reason. I don't think those administrators should be given a pass, no matter how large their employing organizations are.