"progressive" and "centrist" do not have single dimensions to them. basically everyone wants things like healthcare and infrastructure, and people in rural areas are not going to vote for wall street democrats.
Only Wall Street Republicans, of course.
Everyone "wants" things, but everyone does not want things the same way. Centrist Democrat might decide the current Obamacare system is enough, which I've seen some Bernie supporters go apocalyptic over.
Look at how nuanced that subject is alone
That's just one subject. Ask any America how they want improved infrastructure and you'll similarly get a hundred different answers, and a "Centrist Democrat" and "Far Left Democrat" are going to have two entirely different solutions. And I can assure you, one of them will have a solution despised by Berniecrats.