because studio equipment uses 3.5mm or other standard jacks (XLR for microphones for example) as they cause the lowest interference.
Digital signaling is not susceptible to interference like analog signaling. Comparing three analog connectors to a digital signal is a false comparison. With a digital signal unless the interference is large enough to sway the voltage to the wrong side of the threshold it doesn’t matter as it will still register a one or a zero. Analog signaling on the other hand is very susceptible to interference unless you use balanced connections which uses wave interference to remove the added noise.
Digital signaling is not susceptible to interference like analog signaling. Comparing three analog connectors to a digital signal is a false comparison. With a digital signal unless the interference is large enough to sway the voltage to the wrong side of the threshold it doesn’t matter as it will still register a one or a zero. Analog signaling on the other hand is very susceptible to interference unless you use balanced connections which uses wave interference to remove the added noise.