Yeah, that's weird. Plus, it's extra strange that the kerning on the text boxes are different on the back. Note that on the one on the left, the second to last line starts with "a" and ends with "of," but on the one on the right, those words somehow get bumped to the other lines.
the above link had this in it....don't know if it helps or not:
Although past iterations added a subtle design change to indicate the variations, it appears that Panini elected to skip this helpful feature for the main 2021 Donruss Baseball variations.
In some cases for the Retro 1987 cards, there is no apparent difference on the card's front and the only change is a minimal formatting shift on the back. This mainly applies to cards where one word from the bio has been pushed to the next line. It appears the Retro 1987 variation backs are also upside down.