What's the point with that quite lackluster story in Endwalker?

[Kazhar]

Zodiark and Nidhogg aren’t original characters either. Zodiark was a summon in FF Tactics and in FFXII he was a dark-aligned god whose power was limited by light-aligned powers who were fearful of him, just like in FFXIV. Nidhogg was an HNM (sort of like a world boss) giant dragon from FFXI. Killing him even got you the same title in FFXIV as killing him in FFXI did.

I hesitated before I mentionned Zodiark since he's visually so distinct from his FFXII counterpart, but with the Ascians being very obscure FFXII references it's indeed likely the similarities are intentional. I didn't know that Nidhogg was used elsewhere in the franchise though.

Considering Golbez is probably only going to be relevant as a villain in less than a handful of patches, I think it’s fine.

With Endwalker being the FFIV expansion, it's probably the case. It's still more than I would have liked for a MSQ villain. Kuja is my favorite villain in the franchise but I can't imagine myself being satisfied if they just reused him in a completely different game. I'd rather have them create a similar character if that's the archetype they need.
I don't know why I feel as such? I'm not overly found of crossovers for similar reasons.