Because at this point, with this comic, it’s not about holding him to account.
To remix an old saying: "A controversy can travel halfway around the world before the apology has time to put on its shoes". Sadly most outlets who reported on Hank's AI accusations aren't rushing to say "oh yeah he apologized". Maybe they stick it in an update in the article without changing the headline.
The world sucks. So this will stick around much longer than it needed to.