It would be great to see the stats on the stacks.

What is the adoption of the django vs rails or whatever in the sample size?

Is there a difference between companies that reach Series A, B? etc?

Is there a difference in valuation? (On the theory that stack X helped the team iterate faster)

Does it matter what the vertical is? (For instance, are data science companies more successful if they use a pythonic stack?)

p.s. if you don't want to release the data to internet sleuths, you might consider putting out articles like this as content marketing. People will definitely criticize you for your weak study that ignores their favorite factor, but it would be for fun.