“It was just too much risk for the crew,” said Steve Stich, NASA’s commercial crew program manager.

The highly anticipated decision, one of the most consequential by the space agency in years, is a devastating blow to Boeing, which had argued vehemently that Starliner was safe even though it suffered a series of thruster problems and helium leaks as it brought NASA astronauts Sunita Williams and Barry “Butch” Wilmore to the International Space Station in…