There would still need to be ROW, however most of the ROW needed is either already in place due to older, lower capacity and efficiency lines in place (although a lot of this is privately owned), or out in the boonies" of the plains and mountain states where ROW is not so hard/expensive to get (and the Feds own lots of land, and the interstates could serve for HVDC row ... with some caveats/costs)