No. Steering demand will not work. Unless by steering demand you suggest forcibly moving millions of people to Scotland. You have an intermittent power source

No. Steering demand will not work. Unless by steering demand you suggest forcibly moving millions of people to Scotland. You have an intermittent power source (wind), far removed from where the energy is needed, and you do not have sufficient electric transmission capacity. Heat pumps or EVs far removed from the source of generation will not do you any good. You need load where the energy is produced or you need more transmission capacity. The situation GB has is that there is load, and there is enough renewable generation on the grid to meet that load, however they do not have the capability to bring the electricty to where the load is. You can lessen the demand, but the generation would not get less through that. The only benefit of that would be that you wouldn't have to spin up gas plants, but the same amount of wind energy would still be lost.