This is true but also misses the point, in a big way. Which opens the gate for takes like this one:
The salient point - and the one worth repeating - is not that they haven’t proved voter fraud. There are a lot of things in life that you can’t prove with absolute certainty, and but for which there is strong circumstantial evidence and you would do well to assume it’s true.
The issue with voter fraud is not that it hasn’t been PROVEN (which implies that it is more than plausible but just doesn’t pass some strict standard), but that there is zero evidence - none - to create the concern that it is happening on any serious scale. Is it possible? Sure. Is there any basis to assume it’s happening at scale? There is not. None.
It is the same as whether a building will collapse. Is it impossible? No, it is possible. Should some people be entrusted with worrying about it? Sure - that’s why we have building codes and fire codes and inspections and all that. Should we assume that buildings are about to start collapsing, because it is not impossible? Absent any evidence that is happening (not proof - just credible basis), most will agree that is not a wise approach.
Contrast with Russiagate, the essential points of which have plenty of evidence and/or been proven, even if at this point we do not have evidence to secure a conviction for the crime of conspiracy.
The conflation of standards - the proven with the likely with the reasonable - creates fertile ground for demagogues to choose the standard that is convenient, rather than the one that is relevant. When it comes to Russian interference in US elections, what matters is that not enough evidence exists to put Trump himself in jail, otherwise it never happened. And when it comes to massive election fraud, as long as one can’t prove it didn’t happen, it means that we can scream ad infinitum about it despite no credible basis in fact.
I agree with your post, but I think you misunderstood my point.
For PR purposes the Republicans are trying to shift the burden of proof to the negative claim of you can't prove that no fraud or no mistakes happened anywhere. Of course, it's an impossible task.
I compare it to Russiagate because you had many media personalities and journalists floating the possibility that Trump was a Russian agent since the 1980s, that Trump was controlled by Putin with zero proof of such claims. That the Russian bought some Facebook ads and favored Trump is a given, but the claims were far greater than that. Even after all the investigations, without any proof to back up the claims, journalists and some within the democratic party continue to claim Trump is a Russian agent, he's controlled by Putin, the only reason he won was because of Russia.
For the past four years you had many MSNBC liberals saying Trump only won because of Russia, and now we'll have 4 years of deplorables claiming it was a fraudulent election.