The prediction concerns China’s total population by the year 2100. As of today (2025), we are 75 years away from that date, so the prediction cannot yet be judged as right or wrong.

What we can say today:

• China’s population peaked around 2021–2022 at about 1.41–1.43 billion and has since begun to decline.
• The UN World Population Prospects 2022 projections show China’s population falling to roughly 0.77–0.80 billion by 2100, which is on the order of a ~45–50% decline from the peak. This matches the type of projection Chamath is referencing ("contracting by almost 50% by 2100").

However, these are projections, not outcomes. Demographic forecasts over such a long horizon (fertility, mortality, migration, policy changes) are uncertain and can change substantially. Until we actually reach 2100, we cannot definitively determine whether China’s population will have declined by ~50% from its current level.

Because the target year has not arrived, the correct status is inconclusive (too early to tell).