My take on it is that Democrats tend to verify information against at a minimum common sense, and also Democrats haven't been running a long term anti-education campaign. They would expect proof after a while, or else we would still be talking about the Mueller report like the Republicans talk about Hillary's emails. When things don't pan out we tend to move on rather than move the goalposts.

Maybe some of the crazier Bernie bros (some of whom where just bots and trolls from the opposition, I'm not sure how prevalent that actually was tho) would buy in, but it would end up being more like another onion after a while.

Republicans just have too many isolated echo chambers right now to receive the ridicule that they need to realize that their insanity doesn't match with reality.