There has been plenty of debunking of the specific claims. If you have some specific claims that you don't think have been debunked, I'd like to hear them.
There are indeed examples where calling something a lie (or conspiracy theory) is a bigger lie. If this is one of those, you should have no trouble finding specific supporting claims that aren't also lies and haven't been expressly debunked.
I am not claiming the election was stolen or that Trump should have won. What I am saying, is that when you state "Trump's lies about a rigged election", you are labeling his comments as "lies" to dismiss any discussion of the very real problems with mail-in voting. And that denial is your attempt to "dismiss some uncomfortably partial truth", just what I stated in my first comment.
https://www.nytimes.com/2012/10/07/us/politics/as-more-vote-...
If this had happened at large, or really at all, there would be (thousands of) accounts of this, which there weren't.
I'm labeling his lies about a rigged election as such because he specifically claims things that aren't true, demonstrably not true, or simply impossibly true.
Discussing any problems with mail-in-voting is very much still possible, but entirely beside the point.
[0] https://ballotpedia.org/What_happens_if_someone_votes_by_mai...