The crux of the problem for superconductors used as power delivery is the "critical field" problem. [1]
Super conductors are superconductive to a point. Once that point is crossed they turn into regular conductors. (I've seen ~1A cited. For context, EVs charge at around 500A).
To make them useful for power transmission, you'd have to up the voltage to insane levels to avoid collapsing the field.
Superconductors have a critical current density (Ampere/m^2) that varies with temperature and external magnetic field[0]. So if you want more current, you need to use a bigger wire (and/or make it cooler). YBCO HTS tapes have enough current density for power transmission[1].
Super conductors are superconductive to a point. Once that point is crossed they turn into regular conductors. (I've seen ~1A cited. For context, EVs charge at around 500A).
To make them useful for power transmission, you'd have to up the voltage to insane levels to avoid collapsing the field.
[1] https://en.wikipedia.org/wiki/Critical_field