what would that splitter cable be for? They look like 3.5mm to me, I’ve never seen a half inch jack?
Seriously though, odd patch cables are best made in ¼” sizes, but the smaller ones physically limit the use of thicker cable and are inherently weak because while a proper cable clamp is easy on the bigger size connector, 3.5mm size invariably gets yanked out by the cable.
moulded, cheap connectored mass produced cables are my choice for anything 3.5mm. In my broadcasting days, ¼” patch cables were expensive and tough. More than we pay now for a cheap patch bay! For me now, cables are simply disposable. At some point they will break. Open a new packet and move on. I buy unbranded patchbay cables in cheap sets on ebay, Amazon, AliExpress and they’re fine …… until they fail, then you chuck them.
flexible, thin cables are never tough unless they are mega expensive. Look at the cost of a posh patchbay 600mm patch cable.