Having worked in that field for many years I'm personally skeptical that there ever will be an ambient-pressure, room-temperature superconductor. The band structure and interactions that need to be present in the material are just one requirement for superconductivity, the other is that the ground state can actually form and won't be destroyed by thermal noise. However, the strong electron-phonon interaction required for (classical) superconductivity also makes the system susceptible to thermal noise, and in my opinion the thermal noise level at 290 K is just too much even for an ideal superconducting material.