You are correct about the insulation reducing the energy consumption.
Only market forces will drive that train though. Until it becomes cost effective it will never happen. I know that it is really cost effective now in the long run but the advantages have to be seen up front to make the jump. I don’t think they will ever get to the insulation level that you are talking about though. We just don’t build things anymore that are that farsighted.
It’s going to require much more than just putting the insulation in the home. The house will have to be constructed differently to negate the weep problems. Just a vapor barrier won’t do it. I used to build houses and I know what kind of problems insulation can cause even in dry climates. Wood frames have real; issues here so it would almost have to be some kind of masonry/concrete and solid insulation composite construction. That’s a pretty expensive way to go right now.
Trapped vapor is a possible problem to be sure, I was thinking more like insulated panels, say 6” thick urethane within vinyl surfaces, being screwed onto existing exterior walls, over existing siding. Yes, you have fenestrations like doors, windows, hose bibbs, exterior electrical outlets, vents..but the point is QUILT, greatly increasing R values. Same idea applies to roofs.
But it probably is all moot anyway. People involved with the energy business either have vested interests(more $$ from fuel taxes, rising prices)or a blind spot, busy thinking about new sources rather than sinks as thru heat being dumped into the cold winter night sky thru windows. It appears then that the world(of people)will waltz on to oblivion, never seeing the simple answers, like INSULATION; as they sit there with their pet cat in their lap...