I dont know the organization but fwiw they also seem to be supporting this:
https://www.thefire.org/fire-urges-twitter-carnegie-mellon-n...
You can defend someone's right to say something offensive without actually being in support or agreement with said statement.
But the ACLU has changed quite a bit since those days it seems. It's my understanding that they no longer take the "sunlight is the best disinfectant" approach to free speech and the free and open exchange of ideas.