Just wanted to add PBS Frontline aired a very good retrospective on Biden's career last night. I'm sure it's available on line, especially if you have the Passport App ( yes, it's a plug). I have a feeling most of what they aired was already produced before the events of previous weeks. It did point out that at least in the beginning Obama and Biden really didn't have the best relationship. Biden resented being the but of some of Obama's jokes in his speeches.
He was also stung by Obama backing Clinton in 2016. Beau's death also affected him both emotionally and physically more than he lead on.