SPLC is as much a "hate group" as the KKK or La Raza.
You can see this by their own words and actions. There is no compromise with them in their position. Nothing short of the total destruction of any group, statue, or military base will satisfy them.
They are not about making things right, or making things more appropriate to today. Their sole goal is nothing but destruction. And they say so proudly. It is not like they are trying to hide their agenda. They are completely open about their mission to destroy any person or edifice which they deem to be in disagreement with their far-Left agenda.