My first interaction with him was asking about how to backup all data on GrapheneOS (including secure/restricted data). He flat out called me an idiot, said that it "defeats the point of grapheneos", and refused to help. Most of the help formats that he is available on are full of responses very similar to this from him. Hardly by any stretch of the imagination professional conduct.
I do love GrapheneOS and I'm sure managing it as he does/did is quite stressful. I don't have any Ill will towards him, just concern for him and the project. I think stepping down and getting away from social media will be a great move for both him and the project. He clearly wants some much needed time to recover and destress. Frankly, his public behavior was the biggest liability for the project but him stepping down is a good sign that at the very least he is making moves to start recovering.