Agree state subversion seems more plausible than Congress overturning a result itself. And the fact that we're debating how exactly election subversion might take place underscores the threat. Not likely or certain, but unacceptably high.
Worse scenarios are possible. A pivotal state leg dismisses a result it doesn't like based on dubious fraud allegations and sends its own electors + Supreme Court refuses to intervene, saying states decide how to allocate electors. Then Congress just says it's following the Court
I agree the votes aren't there in Congress to overturn an election on Four Seasons Landscaping-level grounds right now, but a veneer of plausibility and/or a shift in the status quo could change the calculations dramatically.
Also this - the risk is potentially long-term and systemic. Eventually low probability events tend to happen.
"alarming local officeholders and opponents who are warning about pro-Trump, 'ends justify the means' candidates taking big roles in running the vote."
Hard not to read article on election official candidates who promote false fraud claims politico.com/news/2021/05/2… in especially ominous terms in light of @drvolts thread over the weekend (though @ZachMontellaro is careful to note constraints on powers of secretaries of state)
Absent fraud, the more prosaic fear is that the chief election official in key states could be campaigning against the legitimacy of the results if their side loses, further undercutting the legitimacy of our democratic system.