I mean, you can call it a privileged viewpoint if you like, but I'm also not going to say it's a justification for what Grimwood and Arios did either just because they lost loved ones in tragic ways. Lloyd went through the same things, too, so he's not exactly speaking from a position of "privilege" anyway. Like he said, undoing all those things would essentially be undoing what made him who he is. Undoing the bad would also undo good things that came out of it.
Like if we're trying to do the philosophical thing of "wouldn't you want to end all human suffering if you could," then sure. But I also don't think Grimwood's plan is actually going to achieve that, much like how the Aureole didn't or Demiourgos didn't. Like with all the Sept-Terrions, they sound great on paper, but none of them have actually worked as advertised. Yes, they can achieve some good, but they aren't going to make all the bad go away.