The SpaceX feed was mentioning as it went up that everything after they cleared the tower was a bonus for them. Looks like they had control even with engines out until they started the flip for stage separation. It over rotated and they couldn't get it to stop flipping after that, so they couldn't get Starship off the booster.
They gave it a couple flips then RUD.
Super cool though. Largest rocket ever to lift off, and they said at the beginning it had 10,000,000 lbs of propellant on board.