When a country makes the one-way generational jump(s) from a TFR of 3 to 2 and then sub-2, and to a post-industrial economy, a bunch of near-irreversible changes set in, from cost inflation and scarcity of education, expectations of years of education and marriage, apartment size etc.

Scott Galloway (and others, like Elizabeth Warren) have been saying this, about the US, repeatedly: US education costs rose (or at least, were allowed to rise by the politicians who were nominally regulating them) by 1400% since the 1970s [https://www.profgalloway.com/inflated/]. This was not sensible policy but if GDP growth via financialization of (third-level) education etc. is your economy's chosen indicator, it's what you get.

Anyway the low TFR is not necessarily a demographic crisis, it's up to the country whether it lets its population decrease (Japan, China), or uses immigration to sustain whatever its target population growth is (US, Canada, EU, SG, Aus).

> 2. Small apartments suppress large family formation (seen in Europe)

You're getting the direction of causality wrong: apartment size was a reaction to the decrease. Contraception, more years of education and other social changes were the drivers of smaller apartment sizes, not the effect.

Education is even worse than that. Education itself is highly competitive even down to the pre-K level in some places.