There is a difference in the rhetoric, between now and then. Sanders is very divisive and not even a Democrat. He ran against Democrats. Listen to his speeches and interviews during a Unity Tour
The Democratic "unity tour" has produced less-than-unifying headlines for the out-of-power party as progressives seek to oppose President Trump and the GOP.
www.npr.org
Listen to Perez:
"Donald Trump is a disaster. He's a threat to our democracy," Perez said. "And I think everybody in that room that we were in in Miami, and yesterday, and the day before, and tomorrow, and through the weekend, understands that."
Listen to Sanders:
"How in God's name are they (Republicans) winning elections?" Sanders asked, exasperated. "And I think the answer to that is the failure of the Democratic Party — to have a progressive agenda, to bring people into the party, to mobilize people. And that's what I'm running around this country trying to do."
During a so-called Unity Tour. Perez was tearing at Trump and highlighting our opposition to Trump. Sanders was tearing at the Democratic Party. That's what he does and it is genuine. Therein lies the difference and why it would be best for all if Bernie were to concede and recede.