Looking through their comments, it's pretty clear they know they're banned, why they're banned, spoke with dang about it at the time, and embraced being banned (I think because they feel it filters out low effort replies? Their statement was on the matter was terse, but semiparphrasing they said "I'm aiming for a shadowban" because "replies are the worst").
I don't get it. How do you know that GP is shadowbanned? The post looks just like a normal post to me; I'm not even sure what it means for it to be dead.
Because "the system" might have made a mistake. And even if the shadowban was warranted at some time, the poster might have improved their conduct in the meantime and should be given another chance.
Usually, when I see a reasonable but dead comment, I vouch for it. If the commenter is shadowbanned and their other most recent comments are also reasonable and civil, I (sometimes) alert them to their status.