Did you miss this bit which was the possible explanation for Okceg's question as to why the chart only showed Trump losses?
"The anonymous person in the link above wrote some code to calculate all the times Trump when down when Biden when up, and to add together all these declines. The result was a loss of 220,833 votes for trump (all numbers are with the data I downloaded today)
The immediate problem here is that it's ignoring losses for Biden when Trump gained votes. If we calculate those, we have a loss of 25,712 for Biden, not really changing things."
I'm sure you'd agree that if the chart (which I am assuming uses the analysis/data discussed at the link) uses only data that shows those instances where Trump's count declined then that is a good and likely correct explanation as to why the chart only shows Trump vote losses?
It would be a shame if all these fine anonymous analysts preparing data on how the Democrats have been "committing voting fraud" were similarly only looking at part of the picture and presenting cherry-picked information in a manner designed to deceive readers into believing there is something criminal going on.