It seems to me that the fundamentally short time horizons of most investors (limited by human lifespan and retirement horizon among other things) results in undervaluing infrastructure and capital investments. Here are a few examples:

1. Homes or apartment buildings may be produced at low quality due to new buyers only planning to live in them for 5-10 years before selling them. This results in higher aggregate housing costs due to increased utilities, maintenance and replacement costs.

2. A large hydroelectric dam or nuclear power plant with a lifespan of 80+ years may not be built despite resulting in a lower overall cost of electricity over a time horizon of several decades or more because it has lower financial returns over the first 20-30 years than a natural gas plant or a wind farm.

Baumol's cost disease as I understand it means that skilled localized labor such as might be involved in large construction projects will often go up faster than inflation, meaning spending today may be more efficient than costs of replacement tomorrow, since inflation of labor costs is high relative to the overall inflation index. If this is the case then we should want to build infrastructure to high quality, to last, and appropriately giving economic credit to a project with long term implications if it is likely to reduce future costs and resource burdens.

Is this question too subject to the value we place on current costs relative to future ones (ie through discount rates) to be objectively answered?

Is the primary solution simply to have government financing for large projects that are deemed worthwhile to society in the long term and how can we determine if these projects are indeed worthwhile with appropriate objective measures of public ROI?

In theory could we expect a shrinking population/economy to financially value large infrastructure projects more due to a potentially negative discount rate?

Tldr: all these are driving at the same general point of does standard financial discounting of capital result in a market failure for long lasting capital infrastructure that results in a less wealthy economy in the long run and how can this be corrected for either when modeling economic returns of a project or creating financial instruments to finance and build long lasting capital.