Gray area, like most things
I get it, but it's a heavily flawed concept. The court of public opinion is fickle and saturated with bias.
I love the idea of holding people accountable, especially people that are in positions of power. Too often, the powerful and influential can get away with doing harmful and outright sickening things because they're too big to be taken down- or at least they think they are.
Not everyone needs to be completely cancelled, though. Some people just need a major reality check. Others have said and done dumb things when they were younger and less mature. None of us were born as enlightened creatures, and we make lots of mistakes as we learn to not be a totally crappy human being. I think if the perceived crime against society doesn't appear to be a dangerous pattern of behavior, it's okay to accept an apology and let it go. I also believe that it's not up to other people to accept a public figure's apology for something that arguably didn't affect them. That being said, not even the groups that are affected can even agree on who and what to cancel, so the waters get even more murky.
I'd say that at least it gets people talking, but that doesn't really matter if the conversations are largely circular.