The public editor doesn't need a supercilious lecture from you on the purpose of comments.
What the comments section"exists for" and what it is used for are two different things.
The  reaction to Renzetti's column is typical of the venomous,  misogynistic comments directed at women columnists and politicians every day in G&M forums. 
A Globe story about Environment Minister Catherine McKenna  a few days ago drew these responses: "McKenna has no concept of what real Science is. She has no business in that portfolio."
And.
"But she is a woman and qualified doesn't matter as long as you have at least 50% of your cabinet made up of women."
Whether it is women's rights, immigration or First Nations issue, there is a cabal of usual suspects on here whose comments are unfailingly misogynistic, racist and insensitive.
No amount of reasoned argument will change their stances. They express deeply felt centuries old biases.
Fortunately, women like Renzetti are not cowed by them.