douglas_Schroeder nailed it....= no consensus on this question.
thus is a well -travelled and oft repeated subject .
AUDIOGON ( do a search for bi-wire ...)
CANUCKAUDIOMART
https://www.canuckaudiomart.com/forum/viewtopic.php?f=6&t=52979
PINKFISHMEDIA/Audio
https://pinkfishmedia.net/forum/threads/connecting-single-cable-to-bi-wire-terminals.236240/#post-38...
In brief
(1) it is entirely system dependent.... and until you actually do an A-B bake-off... you won’t know.
(2) Some speaker manufacturers indeed do favour them (e.g Vandersteen ....) but some of the top cable manufacturers (CHORD, NORDOST....) favour a higher quality single run + jumpers as a better choice over bi-wires at the same price-point. See below
(3) BI-AMPING (with 4 separate cable runs... );;Different story.
E.g. NORDOST
https://www.nordost.com/downloads/NorseJumperinstructions.pdf
CHORD
https://www.chord.co.uk/speaker-cable-guide/
".... Many hi-fi and home cinema loudspeakers have two pairs of binding posts. This allows the speaker to be either bi-wired using two sets of loudspeaker cable or bi-amped using two amplifiers.
As a general rule (and there will always be exceptions) we tend to find that bi-wiring will open out the sound stage and increase perceived levels of detail. However, single wiring will often sound the most musically coherent. There is also an issue with single and bi-wire speaker cables. In all the research we have carried out, a single wire speaker cable out-performs a bi-wire cable of equivalent cost. This makes a lot of sense; the single wire speaker cable has two high quality conductors and the bi-wire cable requires four. So for a given budget, we believe that a single wire cable will always out-perform the equivalent bi-wire cable, so much so that we no longer produce dedicated bi-wire cables..."
TAKEAWAY
Thus there is no silver bullet one size fits all answer.... full stop.