I wouldn’t think that it is that easy. If building a bunch of spamming backlinks to a web page is all it takes to tank it in the SERP then we wouldn’t see many of the web pages ranking where we see them now.
If you carefully read the details of the negative campaigns that were effective, they went far beyond building spammy links. They waged a destructive negative publicity campaign, posing as the owner of the website they were targeting, they contacted webmasters threatening serious consequences if they did not remove links to website targeted in their attack. That particular activity comes dangerously close to crossing the line into criminal activity. At the very least, they have exposed themselves to serious legal action.
It seemed to me to be a colossal waste of money, since they could have saved themselves much time and money by hiring a cracker to hack their victim’s website, just as effective, just as immoral, just as unethical and probably just as illegal.
I seriously doubt, that spammy backlinks alone, will have any significant negative impact on a well-established website.
