If I have my say, I think that the limit of all cables, which are indispensable, unless you have wireless connections, is 0.
The cable is a passive element: it cannot add anything, at most it can take away from the signal.
But I think that its scale of evaluation and consequently of contribution to the signal is from zero to negative.
However, I think that the highly negative cable is a broken, non-compliant, wrong or unsuitable cable.
Then we all agree that there may be "more right" cables for this purpose, in terms of caliber, connection, electrical characteristics.
However, I think that a cable can never make a positive or improving contribution to the system, being a passive "component". the ideal cable carries equivalent chain support to zero.
On the timbre, I couldn't give an opinion: the electrical differences measured are often so small that it becomes a challenge to find audible differences.
But I have a consideration: why do so many people continue to change cables compulsively? perhaps because after a period of getting used to they realize that one and the other are practically identical?
it could, but perhaps what they don't like is the system itself which, if it sounds in a certain way, it certainly won't be a cable that gives it different characteristics...
last aspect: in the hundreds of meters of connection that are inside our system, I find it particular to focus so much on the 4 total meters that are between the wall and the system, between devices and speakers. I would tell you to never look inside the devices themselves....you will never find anything "esoteric"....not even upstream from your main power socket...