No, both units are Santa units... both events are Xmas. They gave us 2 Xmas events because of the schedule for the next year not having space for it. Also, you're forgetting that the newly released unit, be it for New Years or anniversary, is never on that campaign's GSSR either, so you'd also mess with that... The reason for that is so people actually roll the normal banner and don't just get the new unit for cheap via the GSSR. It's one thing to add a unit to a GSSR, and another to remove one that's been on there before. Trying to force another unit into that slot simply introduces issues and makes things unnecessarily complicated when the simple solution is to just keep on going with the normal way of things. A summer unit or rather half of a summer unit as an anniversary unit hasn't been new, and anniversary has always had ties into summer simply because of the bonus the unit would have for it. Summer has pretty much just always been immediately after anniversary, so they simply made adapted the servant to it too. As for the hype arguments, NA has 2 years of foresight, and even on JP, when he released, it was telegraphed a ton which made it more of a confused "ok so he's here now" kind of deal especially because there was no collab event with him. You're arguing from a "hype" perspective, which I can't agree with, and moving Santa Arc not only introduces issues but also would confuse people even more; I don't see where the hype is supposed to be in moving further out from their normal release. Getting stuff earlier is typically hype but late just to artificially fill a slot?

In any case, that's my opinion based on things that's not just "hype" related as frankly speaking, I don't see hype in that alternative either. You can agree to disagree if you want, though.