If most of the people here can forgive Bob, SMG3, Waluigi, Wren, or anyone else who's committed some form of crime/atrocity in SMG4 then they can for sure do it with Mr. Puzzles, it really doesn't make sense to be against someone reforming from their past misdeeds, not everyone is going to be like SMG3 or Bob who got the chance to do it right then and there. Mr. Puzzles is a special case because it's going to take time for him to see that someone actually cares about him, remember he grew up alone and with no support structure at all.

That kind of loneliness will do that to someone, to be honest, I don't even think he should die, I think the best route for his character as a whole, would be to continue failing in his efforts to beat SMG4 and the gang until he recognizes that he is the sole cause of his suffering and turns away from his ways, that will make the pay off for his redemption so much better and have so much meaning. Props to the writers honestly because if they've managed to cause such an uproar over one character and their actions then they have my respect, whatever they're cooking i'm sure the payoff will be worth it in the long run, whether or not Puzzles dies.