It's July 2019 and there's 20 candidates in the field, how well anyone is doing depends on a lot more than polls.
Obama was still 50 points behind Clinton in November 2007, but that wasn't indicative of how he was doing. Sanders wasn't even on the map in July 2015. Y'all need to let this stuff play out. Just make sure that Biden keeps getting in front of cameras and campaigning and shyt and doesn't try to just hide in a bunker and "I was Obama's VP!" his way to the nomination.
My point was that while some recent polls have him in 4th place following the debate you also have this poll showing him in second place only a few points behind Biden. It's way too early to say he's losing ground or that he's done for, as some people have tried to claim in here. I think you and I are agreeing but maybe I'm missing your point.