Donald Trump did win the 2024 U.S. presidential election and began his second (non‑consecutive) term as the 47th president on January 20, 2025, so the condition of Chamath’s prediction (“if Trump were to win”) was met.

However, the composition of Trump’s second cabinet is not “a very youthful cabinet of a lot of 30‑somethings and 40‑somethings.” The core cabinet (vice president plus department heads) and cabinet‑level officials are mostly in their 50s, 60s, and 70s. For example, the Second Trump Cabinet list shows senior posts held by Marco Rubio (Secretary of State, born 1971, mid‑50s), Scott Bessent (Treasury, born 1962, early 60s), Pam Bondi (Attorney General, born 1965, 60), Doug Burgum (Interior, born 1956, 69), Robert F. Kennedy Jr. (Health and Human Services, born 1954, 71), Chris Wright (Energy, born 1965, 60), Linda McMahon (Education, born 1948, 77), and others in similar age brackets, along with Trump himself as the oldest person ever to assume the presidency at his 2025 inauguration. (en.wikipedia.org)

There are some officials in their 40s—Vice President JD Vance (born 1984, about 40–41 in 2025), Secretary of Defense Pete Hegseth (born 1980, 45), Director of National Intelligence Tulsi Gabbard (born 1981, 44), EPA Administrator Lee Zeldin (born 1980, 45), OMB Director Russell Vought (born 1976, 49), and U.S. Trade Representative Jamieson Greer (born 1979/1980, mid‑40s). But there are no cabinet or cabinet‑level officials in their 30s, and people in their 40s are clearly a minority relative to those in their 50s, 60s, and 70s. (en.wikipedia.org)

Because the actual cabinet is older on average and is neither dominated by 30‑ and 40‑somethings nor plausibly described as “very youthful,” Chamath’s prediction did not come true.