It makes some decent points, especially with regards to "forgiveness isn't necessarily about reconciling" and addresses other general misinformation about the idea.
What I always say is "Forgiveness is a gift. Trust is earned."
I think people hang onto a lot of negativity precisely because we so often hear garbage like "Forgive and forget" and "let bygones by bygones" which are phrases explicitly used by abusive people to indicate you are the asshole if you use their track record of bad behavior to be skeptical of their latest empty promises. Such ideas get used to facilitate abusive behavior and tell you that the only way you can be a good and decent person is to set aside common sense and actively cooperate with their plans to victimize you again.
"Forgiveness is a gift. Trust is earned." helps make the distinction between the two things. It can say "I may no longer be mad and projecting a lot of negativity at you, but you haven't fixed anything at all from your end, so, no. Don't assume that means I will be a chump and fall for your garbage."
AKA: Fool me once, shame on you. Fool me twice, shame on me.
It's okay to say "I was burned by this person. There is zero evidence that they have changed and I will not trust them again." while also saying to yourself "I am sick to death of wallowing in my misery. I would like to leave this emotional pain behind and focus on other things. I would like to stop and smell the roses and be present in the here and now and enjoy today, regardless of what shitty things some asshole did to me in the past."
TLDR: Sometimes, clinging to old pain is a means to shield yourself from new harm. Realizing that can help empower you to protect yourself without wallowing in misery.