I hear this sentiment all of the time as well, not just restricted to cases of libel but it seems most common with libel.
It doesn't matter if something is written down as being against the law/regulations/whatever if the punishment for breaking that law/regulation is toothless, seldom applied, or so expensive to get proceedings started that 90% of the population is priced-out of pursuing their case from the start.
"Just sue them if they write something incorrect/defamatory/etc" is not really a realistic option for the majority of people, not a guarantee of anything happening or reforming, and generally the damage has already been caused. No one really cares about a retraction issued a few months after a story is released, we've all moved on to the next outrage-inducing story.