There’s no urgency, in part, because he has no serious opposition in the primaries.
Things could change as primaries get under way. Remember LBJ in 1968, where Gene McCarthy did very well against him in the New Hampshire primary. That likely helped LBJ decide to not run for reelection.
If this Minnesota congressman does well in early primaries, that could signal that Biden will give it up. Otherwise, he will be the Democrat nominee.
I was a 17 year old McCarthy field worker in NH in December and January 67-68.
Glorious times.
Most people don't know that Bobby held back until LBJ quit, but we were not working for RFK, not even a little bit - we were SO PISSED, it felt like we did the heavy lifting to make something happen that no one believed possible, so that "another Kennedy" could step in, pick up our chips without asking, and be the nominee.
As late as the awful night of June 4, 1968 it was still a race, McCarthy won Oregon that night but RFK won California.