With lots of data there's no doubt that they are measuring something, but it's not clear that they are measuring what they want.

Your breakfast analogy would be more like:

- Some days Alice eats crumpets while sitting in her house and it takes her about 20 minutes.

- Some days Bob eats a bagel while on the way to work and it takes him about 5 minutes.

- Therefore, bagels are 4 times faster to eat than crumpets.

See the problem is we have conflated lots of correlations at once. There is 1) a tendency for certain types of foods (languages) to be used for certain purposes, and a tendency for certain kinds of people to prefer certain foods (languages), and neither of those correlations are necessarily caused by the properties of the food (language) itself.