I'm not convinced RTSC will be immediately applicable in fusion reactors. Wendelstein 7-x is using helium cooled superconductors even though nitrogen cooled sup

I'm not convinced RTSC will be immediately applicable in fusion reactors. Wendelstein 7-x is using helium cooled superconductors even though nitrogen cooled superconductors exist, but apparently they lack some necessary properties. What if the RTSC is too brittle to make wires out of it or something like that?