Joe Biden was a lame-duck the day he entered office. He has pledged not to run again in 2024 but even if he breaks that promise he'd wouldn't be viable (let's be real - many feel mentally he's not viable now never mind 4-years from now).
VP Kamala Harris is very unpopular. Her only hope is that her stature as VP combined with no other candidate emerging as the clear consensus will clear her path to the nomination in 2024. The Democratic machine will back her as the nominee under those circumstances.
Any tall poppy on the Democratic side will thus have to be brought down by leaks, rumors, innuendo, and smears. Which is why after months of silence I believe the media is now having open season on Andrew Cuomo and his handling of the Corona virus nursing home deaths. Governor Cuomo is a well-known name and therefor a threat to the VP. The sniping the next few years will be very entertaining.