[clarry]

> I'd argue that ease of use and readability are perfectly quantifiable

Do we have any objective metrics? The only thing I can think of is all the (inconclusive) studies about error density. Unfortunately error density is a very far cry from measuring the overall quality of a software product, or the mental effort that was required to produce it, or the mental effort required to maintain it.

> there are thousands of people whose job is precisely optimising usability for many products

Yeah but programming languages are more abstract; they're tools of thought (just like mathematical objects), and optimizing their use is nothing like observing a user press the buttons on a machine to get themselves a cup of coffee.

Controlled studies are very difficult to run, for obvious reasons. (Unlike for the coffee machine)