The PA, WI, MI GOP state legislatures refused to process mail in ballots before hand which is why it took so long. Look at Florida who voted R and counted their mail in ballots before Election Day and were able to report results that night. It was manufactured by GOP state legislatures to sow doubt.
Sources:
https://www.google.com/amp/s/www.foxnews.com/politics/pennsy...
https://www.google.com/amp/s/www.forbes.com/sites/alisondurk...
https://www.npr.org/2020/11/04/931136905/we-ll-be-working-24...