Yes, and for short haul that works fine. But for really long haul it doesn't, hence HVDC so that's what you compare with: the situation where it makes a difference such that extra cost incurred doesn't immediately invalidate your option. HVDC is much better comparison material than your average overhead powerline. For the same reason we don't compare bicycles with trucks for long haul cargo but we do compare bicycles with cars for shorter distances and personal travel.