I find these takes very interesting.
Personally, I find that what cql shows is way less limiting than you pointed out, though. cql doesn’t give you an explicit, verbal explanation but Suibian sealing itself happens during a very specific time-frame, which is quite telling. It’s a period of wwx’s life when he lost everything and he still managed to get back up, when he showcased incredible strength as a person and cultivator (just not necessarily core strength) and incredible loyalty.
You can theorize a lot around that. Add to that some observations in its behavior and some of the things said/shown in cql re: swords and other spiritual tools, and you get a very interesting take on cql Suibian.
When wwx gave jc his core, he had to undergo something which nobody until then would’ve gone through willingly. Losing a core is painful both physically and mentally, but giving one away is somehow even worse, if you think about it, because the loss is not immediate at all. You have to willingly let yourself be basically mutilated, feel the core leave your body and keep that awareness and willingness at 100% until the process is done or risk the procedure to fail.
And immediately after that, wwx was thrown into the Burial Mounds, a place where nobody survives, yet he managed to survive it. Not unchanged, but he’s a survivor.
All of this shows incredible strength of character, as well as a high level of intelligence (by looking outside the box for solutions when inside there are none. wwx trains in a new form of cultivation and masters a lot of it in a few months. He also starts modifying talismans or creating new ones with very successful results, and remember that talismans were part of his cultivation before he gave up his core).
This is the time-frame when Suibian decides to seal itself.
Cql talks about sword spirits (and not only those of the swords, but other tools as well), loyalty, respect and connection to the cultivator who is accepted as a master a whole lot.
Suibian’s canon loyalty, that goes beyond an affinity to the core, is confirmed by the fact that yes, it allowed jc to draw it out because he has wwx’ core, but if it depended all on the core and its strength in order to determine its behavior, then it wouldn’t have let itself be drawn by wwx himself after giving away the core.
So imho it’s clear that cql Suibian takes into account wwx’ person AND character, not just his core and its strength (and to be fair, even in the other adaptations, what is said on the matter seems more like a series of theories, because the occurrence is so rare, so it’s not like what is said is set in stone).
To me, the way this all was framed makes it look like Suibian lets itself be drawn by jc because wwx himself willingly gave away a part of himself to jc, hence Suibian not only recognizing the core itself, but also the act of loyalty. This is why despite letting itself be drawn by jc, its master still remains wwx. This shows a certain level of sentience in Suibian.
This theory about loyalty and sentience doesn’t seem far fetched when you consider how they showed Zidian choosing its masters. Its first master (that we see on screen) is Madam Yu. Then it accepts jc as a master BUT it still is loyal to Madam Yu enough to obey her after the transfer because jc’s well being is at stake. Not only that, but it temporarily accepts Jiang Fengmian as a master for those same reasons: loyalty to Madam Yu and her decision, and the prioritizing of its new master’s well being.
This shift based on loyalty and priorities also shows a certain level of sentience. I don’t know how sentient these tools are in the other adaptations, but cql SHOWS a lot of it (less explicit telling). Not only that, but cql shows quite well through various tools that each weapon’s spirit has its own personality, thus different ways to approach the idea of master and loyalty.
TLDR: cql Suibian sealing itself when wwx gave up his core and was thrown in the Burial Mounds, and it letting itself be drawn by jc but still keeping wwx as its master despite the lack of core, shows that Suibian is loyal to wwx and values his strength beyond that of a core as well as his own sense of loyalty, thus the spirit of the sword reflecting characteristics of its master. Despite wwx not being able to wield it in combat, cql Suibian is still proud to have him as its master.
I hope my ramble makes sense. I’m not as coherent as I’d like to be at the moment because of tiredness. I apologize for eventual typos.
