Did Disney jump the Gunn?

Gunn's 'Guardians of the Galaxy' films were enormously successful for Disney, and started the Marvel movie universe as many people know it. But ultimately the family-friendly company decided that Gunn couldn't stick around for a third film after these tweets were brought to its attention. However, Disney did hire Roseanne Barr when she also had awful, and much more recent tweets. This also points to a failure to do due diligence on Disney's part if they did not know these tweets existed when they hired Gunn in the first place. In the meantime, filmmakers hoping to make it big are now rushing to delete their Twitter history.