The only anecdotal evidence I've linked is Stripe's experience with Sorbet. The paper linked is an actual scientific analysis with great study design. I couldn't find the Airbnb slides or talk but an engineer involved claims the study was carefully designed[1].
> When you look at reports of bug density across large samples of projects, it's clear that TypeScript does not solve any problems. See https://medium.com/javascript-scene/the-shocking-secret-abou....
Go read the "study" referenced in that article. It's just blog post with a terrible methodology. It's basically
(number of issues with bug label) / (lines of code)
The author doesn't even normalize for LOC (larger codebases tend to have more bugs) or take into account project complexity.
[1]: https://twitter.com/swyx/status/1094857103863209985
EDIT: add disclaimer about airbnb talk
The other study you referred to sponsored by Microsoft is very vague on the methods used to conduct the experiment. So its not repeatable. You can't say something is scientifically true unless the results are repeatable.
bugs are (in part) function of code and tooling complexity, making some bugs harder to introduce doesn't reduce that complexity. risk compensation principle is another factor, and so on.
i haven't yet seen strong evidence that static typing really reduces bug density.
I don't buy these hypotheticals and also I don't believe in this kind of anecdotal evidence.
I think that the real root problem is that they didn't break down the code into logical components and didn't test them correctly - That was the real problem, not JavaScript.
When you look at reports of bug density across large samples of projects, it's clear that TypeScript does not solve any problems. See https://medium.com/javascript-scene/the-shocking-secret-abou...