True ,know first hand
A good person can do bad things and a bad person can do good things. I don't think anyone is deciding (or at least should be deciding) what kind of person Tischler is just based on his recent spat with Kornbluh. To give him a free pass based on previous good deeds would be just as wrong as ignoring those good deeds because of other negative actions.
The fact of the matter here is, he has been rabble-rousing (for good or bad, matter of opinion), he has made threats against Kornbluh (again, justified or not, matter of opinion), and actions have consequences.