Actually, most layman do care about it, but short-term KPI-driven management (in the private and public sector alike) don't, because as you say they don't have the proper incentives.
Part of the problem is information, in that it’s hard to know how long things will last. But I think this is secondary to most people being short term focused. I’d love to see a building company offering special materials for an extra long design life, but I doubt many people would be interested.
By the way, laymen did and do pay for buildings made out of brick which can last for 100s of years.