Planned Parenthood could even have reversed the tables on the NF people. They, or their affiliates, could easily make a similar page that lists the names of vehement anti-abortionists, adorned with pictures of dead doctors and mug shots of their murderers. They could have embedded the page. They could have used it. Rights, including the right to free speech, can always be abused.
Free speech is indeed indivisible.
You cannot modify it. It is the only thing. Restrictions on free speech on other grounds than the personal moral and responsibility of the speaker , will bring free speech down and undercut the principle itself.