backgrounds and viewpoints, so there's...wait for it...."friction" between them...imagine that.
Also, as the article points out, Obama had little luck striking any relationship with Mitch McConnell...yet, Biden...with his decades of relationships in D.C...plus his collaborative mentality, was able to get Mitch to stand with him at a bridge project unveiling at the outset of the. "Bipartisan" Infrastructure Bill implementation....so no one can say that JB messes "everything" up...and I'm sure Barack would acknowledge that...even if you won't ;-)
Don't be averse to a little "Critical Thinking"...especially when it comes to politics.