You’re not wrong, but he’s the incumbent. They were never going to switch him out. He beat Trump last time, and there’s no way the DNC was ever going to float someone different. Hillary was not the incumbent.
But man it would be awesome to have “Yes we can” slogan energy back again. The speeches on the runup to Obama’s first presidential election were so morale-boosting. I ended up canvassing for him when I lived in northwest Indiana with my baby in a stroller and my toddler walking around with us. It was awesome.
Now I mostly just vote and get really upset a lot.