I don't think everyone can't really comprehend what it would do to foreign relations if Biden was proven to have won by cheating. Every single First World nation would be rendered unable to meet with him. He wouldn't be some tinpot Third World rando, or even a Second World "elected" president like Maduro. The slightest bit of legitimization would immediately crater foreign heads of state. Why? Leaving aside memes of "muh democracy", which really aren't just memes but a myth made reality, given their own domestic issues and rumblings of discontent the slightest hint they'd be okay with First World election fuckery would cause national uproar. You think France is bad now? Just see what happens if the people think Macron is willing to blatantly (key word here) cheat to stay in power. Now repeat for Germany, Sweden, etc, any nation that's shown signs of willing to step on the people for voting wrong. The idea that they would be fine with openly disenfranching voters would lead to internal collapse as their own legitimacy vanishes.