Agreed, could Obama have done more? Of course, but the loss wasn't his fault when the Clinton team spent so much time raising money and not trying harder to relate to the voter base. Obama came out in his campaign and had a clear message, Hope and Change. Trump did the same with his message, MAGA. I don't even recall what the Clinton message was. Yes Queen? I'm with her? What was she trying to drive? I'm not saying that not having a catchy message was the only issue, but she failed to capture the fan base in a way that would rally people to come out and vote for her.
She presented herself as very cocky during the debates with all the excessive smiling and laughing, she didn't relate with the poor/jobless victims with her big fundraiser parties in California with the extremely high entry price and high profile guests. At the end of it all, they were responsible for delivering successful messaging and rallying the base to get them to victory and they failed.