IIRC, antopodal HVDC would have resistive losses of either 70% or 30% — I’d have to recalculate from scratch to find out which, but it doesn’t matter much either way: the real issues are “How much does the line cost?” and “what are the political implications of that size power line in all the places it has to pass through?”

Batteries and HVDC to your nearest major desert are what I expect to be the solutions.