The primary beneficiaries of the [Baukindergeld] are buyers of existing properties in rural areas. Tendenitally, it will likely lead to further rising construction costs, as construction companies will correspondingly try to enforce cost increases.
The challenge in building or buying a property for personal use for many families is that existing equity is tied up. Equity that would actually also make sense for later retirement provision, e.g., invested long-term in stocks and ETFs.
Very few home builders then have enough money left to reasonably provide for old age. And owning a house is nice, but rarely a truly suitable retirement provision, since a kind of second rent is always incurred.