re: How did Biden get elected President? Why?

I agree with most here that he could be controlled and not really a controversial pick. Biden was likeable old man to many. Was a prior VP and public could support him. Warren is not likable, Sanders is a communist, Harris couldn't even get 1%, etc etc. Of the group Biden had the most appeal for the gen pop.
Couple that with them knowing they could control him and put the Obamaites in the administration to run policy, he was perfect. The dementia was a feature not a detriment.
I also think they had enough dirt on him and questionable dealings, not too mention Hunter's dirt to get him out of the way if they needed too. In the end if they had to go to dementia to get him out of they way, they could do that. They are exposing his dementia more publicly now to do just that.
The media and everybody knew he had dementia in 2020. THey have played the good little soldiers keeping it hidden the best they could from the public. Well I think they are now being good little media soldiers and doing the DNC and powers in DC bidding to get him out of the way.