Thank you for raising this request, @Becca_Perry 
I see! Definitely agreed that being able to quickly switch date granularities in data tables and pivot tables would be very handy.
We call this feature Widget Date drill, and true that it’s only available for non-tabular charts at the moment.
I have noted down in our product backlog for later improvements. Will be sure to get back when there’s any update.
As for a workaround: you can set up Dashboard Date drill, and map it to your data tables and pivots.
Let me know if this workaround suits you, Becca.