Why not? Lore status does not matter in the slightest. In terms of gameplay, it's still a single Pokémon.And so what if this means you need to have completed two different games to get this thing- it's the literal god of the Pokémon world, what do you want them to do, just hand it to you on a silver platter?
Alternatively, they could just have given you the Azure Flute after beating Cynthia, no additional game required. That would have been DRAMATICALLY better.
So it's perfectly okay that someone that gets Legends has a chance to get two Arceus (thus, a redundant reward), while the ones that don't cannot get any?They didn't have to implement the Azure Flute event at all. We are not entitled to it. They could have easily deemed the Arceus we get in Legends: Arceus to be enough for us and left it at that, but they didn't, and now people are complaining because this previous completely inaccessible event isn't even more accessible than they saw fit to make it? I'm sorry, but that comes off as entitled to me and it doesn't sit well with me at all. I for one am happy that we got the event at all.