Oh no, absolutely not.
The Democrats sabotaged themselves to an almost inconceivable degree. And they've been doing it for years. Although, as much as I love Bernie, I don't think he would have beaten Trump.
Nor did Hillary, or course.
My issue isn't with the Democrats losing, in many ways they deserved to lose. If the republicans had nominated a sane candidate, somebody who wasn't so obviously a wannabe-dictator and narcissist, I'd have very little issue. But they nominated Trump.