• Joe Biden formally announced he would seek reelection in 2024 and proceeded to run in the Democratic primaries, where he won an overwhelming majority of delegates and became the presumptive Democratic nominee, easily defeating challengers including Rep. Dean Phillips. (en.wikipedia.org)
• Dean Phillips mounted a long-shot primary challenge focused largely on Biden’s age, but he performed poorly (e.g., about 20% in New Hampshire while Biden won via write‑in) and failed to gain traction in subsequent contests like South Carolina. (apnews.com)
• On March 6, 2024, Phillips ended his campaign and endorsed Biden, explicitly acknowledging that he was not the alternative Democratic voters wanted. (reuters.com)
• Only after Biden had already secured effective control of the delegate race and become the presumptive nominee did he later withdraw from the 2024 general election on July 21, 2024; Vice President Kamala Harris was then made the Democratic nominee. This later withdrawal does not change the fact that Phillips never defeated Biden for the Democratic nomination and, in practice, never came close to doing so. (en.wikipedia.org)

Because Biden did run in the 2024 Democratic primaries and Phillips was unable to seriously challenge, let alone defeat, him for the nomination, Friedberg’s prediction that Phillips “doesn’t stand a chance” against Biden under those structural conditions was borne out by events.