It seems the breakthrough is that you could use familiar semiconductor manufacturing processes. However the temperature is still going to be a major issue. I don't want a computer that requires liquid helium cooling.

> I don't want a computer that requires liquid helium cooling.

True, but I /can/ see someone, such as Sandia National Labs, very much willing to install a liquid helium cooled computer if it provides a significant performance increase above their existing supercomputer installations.

> you could use familiar semiconductor manufacturing processes.

Unclear to me why that's helpful. Materials that superconduct at a higher temperature than this one aren't hard to come by, or obscure:

> In 1913, lead was found to superconduct at 7 K,

Probably because they don’t behave well for normal lithography techniques? The high temp superconductors I know of are weird meta materials, and good luck getting them to exist in chip form at all.