Ignore only hides his posts but your posts still can be seen by him and reported. You can't even report him if he scold you or take potshots at you because his posts cannot be seen.
I have a stalker behaving this way for 2 years, appear in every threads that I was in and take potshots at me. He thinks he is smart by harassing me this way to avoid infractions.
If I had put him on ignore list, he would have gone on forever and there is no repercussions to change his behavior. I did not rebuke him at all and this continued for 2 years.
He could have put me in ignore list but no. The perpetrator should be the one putting me in ignore list and not the other way around.
Even if you put him in ignore light he can still passive aggressive click on

emote or like the post when he use his clone to scold you. I'm sure many of you have encountered this.
so the ignore function is quite useless if it is not mutual
The victim is actually on a disadvantage.