Let me add though, that in some cases and in some races, what you claim may very well be true. But I seriously doubt that across the board and in dozens of Congressional districts across the nation, it was simply a matter of what you claim.
We both remember that in 2010, Democrats ran against Obama and Obamacare. The result was losing the House.
We both remember that in 2014, Democrats ran on "bipartisanship" and the Sequester and deficit reduction. The result was losing the Senate.
We both remember that in 2016, Democrats ran a moderate technocrat who opposed Medicare for All and a $15/hr minimum wage. The result was losing the White House.
We both remember all of this because it wasn't that long ago.
So what I don't understand is why you think "moderation" will work this time, when it didn't before?