Clarifying something that I was unsure about, any possible confidentiality agreement that the Yankees could put in place would be for managers and coaches. Player contracts are governed by the Collective Bargaining Agreement, which does not allow for these type of agreements.
This would still allow players to write memoirs and tell-alls. Which is good. I am excited to read Derek Jeter’s memoirs, which I’ll guess he’ll release 2-3 years after retiring.