Segnosaur
Penultimate Amazing
First of all, keep in mind that that 70 vs. 70.5% seems to be just an average.I think 70% and 70.7% can reasonably be called "roughly the same"."Roughly the same" is doing a lot of heavy lifting.
The referenced article breaks things down into separate battleground states, and the change in Arizona and North Carolina were 5 and 2.5% respectively.
Secondly, looking at total voter turnout may be a little misleading. After all, some former democratic supporters might go to the polls and vote republican, or 3rd party. Or drop in democratic support might be combined with an increase in republican support for unrelated reasons, leaving the total number who voted roughly the same.