I probably should have left this alone.  But for some reason, I just couldn't help myself.

I think there's some confusion about the passive voice here. "unfold" is actually in the active voice in this case. By changing it to "was perpetrated by", I think you have actually changed it from the active voice to the passive voice.

— Joel Swagman (@JoelswagmanJoel) January 30, 2022

You could say "British soldiers perpetrated Bloody Sunday" if you want to avoid the passive voice.

— Joel Swagman (@JoelswagmanJoel) January 30, 2022