Its not that easy to narrow down what the scope of a University's expertise would be though - take Victoria University of Wellington. Let's look at say, the Arts department because they have one and I know some about it.

Would you say that VUW can thus allow expression on any topic of study that Arts schools typically study because the methodology across any of the specific topics is broadly lumped together?

Or, is it no, they can only talk about History, if within the Arts school they have a History Department? Well in that case, should they be expressing opinions on all of History, or only on those areas of History that they actually study?

OK well within that History department they are teaching courses on Pacific History, US History, some periods of European History so they can only opine on that.

Or should they only be allowed to talk on the specific periods / topics of US History that they are running courses on? Or should they only be allowed to talk about particular methods of Historical study when called upon so Dolores Janiewski (who was an awesome lecturer 20 odd years ago when I was there) is only allowed to talk about I dunno 20th Century US Feminism?

Realistically the people who could determine whether or not someone has enough expertise to be considered an expert opinion are the Universities.

Re the WCC asking the Government to butt out, that isn't a matter of expertise but more one of jurisdiction, democratic rights responsibilities & freedom than a matter of free speech.