Charge-density waves destroy the superconductivity in ceramic cuprates https://www.mpg.de/7684681/superconductivity_cuprates
There is a growing understanding of the conditions required for superconductivity and how it can be achieved at realistic temperatures.
Frano, M. M. Yee, Y. Yoshida, H. Eisaki, E. Schierle, E. Weschke, R.