Available data show that U.S. tariff revenue has risen sharply but has not yet actually reached the $400–500 billion range discussed in the prediction, and the forecast horizon (“late‑2020s, once fully ramped”) has not arrived.

Key points from current data:

• For FY 2024, federal customs duties were about $77–83 billion, well below even $200 billion. (usafacts.org)
• Through August 2025, FY 2025 customs revenue totaled about $165.2 billion, already a record pace but still far from $400–500 billion on a realized 12‑month basis. (usafacts.org)
• Other reporting on FY 2025 indicates net customs receipts a bit above $100 billion through June and around $195–215 billion for the full fiscal year, depending on how one counts newer tariffs—again, materially below the $400–500 billion range. (voice.lapaas.com)
• In October 2025, monthly customs duties hit a record $31.4 billion, which, if simply annualized, implies something in the high‑$300 billions per year; some officials now project tariff revenue of around $400 billion in FY 2026 and even suggest it could exceed $500 billion annually. But these are projections, not realized receipts, and depend on policies and economic conditions holding through the late 2020s. (reuters.com)

Because (1) actual annual tariff revenue to date is still well below $400–500 billion, and (2) the prediction explicitly targets late‑2020s, once fully ramped, which is after November 30, 2025, there is not yet enough realized history to say whether annual receipts will in fact sustain the $400–500 billion level by that time. Therefore, the prediction’s accuracy is inconclusive (too early to tell).