From what I understand, the main technological blocker (as opposed to various political and economic blockers) is the need for superconductors to achieve reasonable energy efficiency. With cheap energy, that's less of a pressing need (and further, cheap energy = more energy to throw at cryogenic cooling systems to induce superconductivity in less-exotic materials).

Superconductors are also used for thermal reasons. Generating strong magnetic fields through high current in a resistive material will put out a lot of heat.

Cheap energy = more energy to throw at cooling systems, per above.