It would be helpful if he included actual numbers in the article instead of just posting links to external sources that may be unreliable or subject to change.
The Pennsylvania SURE report for 2020 indicates that 6.945 million votes were cast. I believe the final official results for the presidential election had 6.915 million total votes for the three candidates on the ballot in PA (Trump, Biden and the Libertarian Party candidate).
Where does this guy come up with 90,000 or 121,000 “extra” votes?
Judicial Watch had an observer present during the ballot count for Allegheny County (Pittsburgh) in 2020.
Subsequently they sued the state and almost 200,000 names were removed from the registered voter rolls.
It looks to me like there are more total votes cast than voters WHO VOTED. Not voters who were registered.