The backlash of Joe Rogan's "endorsement" of Bernie in the face of a movement like "vote blue no matter who" is fantastic.
Splintering just like 2004.
I still think the best course of action is for Bernie to work with AOC. Groom her 4 years. The timelines do line up where she could get reelected and then be free of Congress in time for her inauguration.
Age? Sure she'd win at age 34, but she'd be 35 by her inauguration.