Is it true: Boeing CFT Starliner stranded astronauts (2024-25)?

There's no solid evidence for it.

The claim does not clear the evidence bar. The long stay (286 days instead of a planned eight to 14) is undisputed background: Starliner failed and NASA judged a crewed return on it too risky. The claim itself has two limbs. "Abandoned" is contradicted by NASA's record: its FAQ says the docked SpaceX Crew-8 Dragon served as the emergency return spacecraft until Crew-9 arrived, and its 24 August 2024 announcement assigned the astronauts to Crew-9. The political-motive and earlier-rescue limb rests on statements by Trump and Musk. CNN reported that NASA's Steve Stich said the next Dragon able to bring them home was the one that did, and that Joel Montalbano said NASA was "already looking at options" when the President asked in January; a former senior Biden White House official and a former senior NASA official told CNN they never heard of Musk's alleged offer, and CNN found "no publicly available evidence". NASA's own March 2025 release credited President Trump's direction with pulling the return schedule forward by a month, well short of the "several months" Musk alleged.