I don't think the OP means it would be great because we can leave our heating on all day and just wear bathing costumes in the house.

It's more what it enables in terms of industrial production, and transportation and the knock-on effects from that.

Again though, diminishing returns. My life would be better if Bolivia puts in better transit to in their mountain villages - but not by much since I currently believe I will never go there and so it is a just in case. Even for the people who live in those places the population may be so small as to not be worth the investment even if energy was free.