I really don't think Lewis is retiring anytime soon. Stranger things have happened but he's given no indication that he's ready to leave. It seems Angela leaving is just a coincidence that is happening alongside Mercedes struggling.
Also wanted to point out his standout moment in the press conference yesterday when most drivers were doing the "yeah it's definitely better here now and we feel safe, so much progress being made, etc" and Lewis was like "I think the opposite of what everyone just said."
Love him.