You are not in any kind of position to recommend what the Globe should do to have credibility.  

"Alt-left" has no meaning whatsoever - just a made-up word to counter the term "alt-right" coined by white supremacists to describe themselves.  

You don't get to tell an opinion writer how to have their opinion.  It's their opinion!

There is no such thing as "all sides" if you mean to give equal weight or any weight at all to someone's opinion (i.e. vaccines cause autism) when discussing facts (vaccines are proven to save lives and limit the spread of contagions).  To do so is a failure of logic (false balance).