It’s very simple: Apple has been stagnant since Cook took over. Talented employees want two things: to work on interesting projects and to win. Apple hasn’t done that in a long time.
Meanwhile Elon has built the most advanced spaceships, EVs and is a leader in the two most important emergent technologies: robotics and AI. That’s the result of one man’s will and vision, similar to how Apple was under Steve Jobs; and neither have a reputation for treating their employees well, but they took their BS because they were building cool stuff and winning.
I’ve been saying this for years now. Tim Cook has been one of the worst CEOs and Apple is one super AI smartphone/device away from becoming the next Blackberry.