When configuring a FILTER tool, the results of your formula are uncertain until you RUN/PLAY the workflow. Compare that experience with the configuration of a FORMULA tool where you see a "Data Preview" of the first record results.
TRUE or FALSE could readily be added to the Filter Tool and save the execution time for the workflow.
When you get to HTML tool versions, you could check many rows of data and potentially give back counts of TRUE and FALSE results as well.
I'll put this on my x-mas list and see if Santa has me on the naughty or nice list.
Cheers,
Mark