That's where you are wrong. Due to his depression, he is physically unable to perform. If he needs to leave his JOB to fix his LIFE, then so be it.
See above comments for Schilling's sock and Rondo's elbow. Throw KG's right knee and both of Amare's knees while you're at it. Just because you have a medical condition doesn't mean you're physically unable to perform.
Having a medical condition does not mean you are medically able to perform either. Try hyperventiallting from a panic attack due to anxiety and then imagine running around a basketball court while being unable to breathe.
Look, Sanders shouldn't have self-medicated by using marijuana. And per the terms of his contract, he cost himself about $1.5 million in fines due to suspensions. But depression is a real thing, whether or not you'd like to admit it, and an arbitrator ruled years ago that the CBA does not enable a team to void a contract because of it. Knowing that, the Bucks and Sanders agreed to end the contract. The Bucks win, because they are now out only 50% of what they otherwise would have been, and get to keep that money from counting against the salary cap. If they'd suspended Sanders until he played, they would have to still give Sanders money to charities agreed (they can't just keep the money), and his salary would count against the cap. Sanders wins because he can move on with his life. It's an imperfect world.
Also, I'm not trying to speak for anyone else here, but I imagine one reason some posters here call Sanders courageous is because either they or someone close to them has had to deal with severe depression or anxiety, and know first-hand the amount of strength it can take to expose yourself to the public ridicule that mental health disorders seem to attract. As your and other posts have served to demonstrate.