Because the stated reason for saying Bernie can’t compete against Trump is a lie. In reality, many of those opinions are biased because the person is somehow hooked up in Democratic politics and they know that once Bernie takes over, it’s curtains for them. And further feeding at the trough.
Here is an example: that guy who wrote the app for the Iowa caucus? He was paid $54 grand. Did he know anything about what he was doing? Hell no.
In an ideal world, the Democrats would have started planning and testing that app a year ago. There is no reason they could not have done so.
The Democrats are all too chummy and way too easy to pass out donation dollars. Comraderie and being on the inside is the criteria for them; it’s certainly not doing the job for constituents.