Lately I feel all the Excalibur wank hurt it more than it helped.
When I see Durindana, it doesn't have much to it. Just a powerful unbreakable sword (which Hektor added an extended grip). It is powerful, it can block even Artemis' arrows but nothing like being made by the planet to protect the world and stuff like that.
So there aren't many ''buts'' on it. It gets to have multiple wielders and each of them using with differently.
Meanwhile Excalibur is so special that it's a plot point that Richard is just larping. It could have made a really cool confusing plotline with another guy wielding Excalibur but we don't and likely never will. Most we get is that Castoria's profile alludes to the tales Gawain is the wielder noting Artoria wielded Marmyadose while she lent Excalibur to Gawain. That's it. Likely won't ever serve any purpose because Nasu's Britain autism only uses them in super serious situations once in a blue moon.