Micay did not step down nor is it a symbolic gesture. He removed himself, at the demand of others within the organization, from any public relations duties he once held. He is an excellent and talented engineer and an absolutely horrible representative.
He has no people skills. He does continue to contribute and guides the project privately. It should have been done long ago because I think he has done a lot of damage by overreacting and fostering a community of toxicity by being a bad example.
Since his departure it has been improving and GrapheneOS is becoming mature and a far cry from the Copperhead days.