The same could be said about flowers.com, macys.com, or literally any company doing business on the internet. Scale is basically a solved problem so pretending that AirBnb is a "Tech Company" or that they have any interesting tech is incredibly naive.
Once macys.com gets a page with all the tech they open-sourced that is actually used at a ton of places outside of the company, similar to that of Airbnb[0], then we can talk.
Out of the ones I personally worked with, Enzyme[1] is pretty much the de-facto industry standard for writing React unit tests. Airflow[2] is used very commonly (our team at a big known non-tech company I used to work at used it about 5 years ago), and so is Lottie[3]. And these are just the ones off the top of my head, given that I actually got to use those. They have many many more that seem to have a pretty high usage. And their tech blog is very insightful, I learned quite a bit from it myself when it comes to my development skills.
And no, I neither was nor currently am employed by Airbnb, not a big user of theirs, not paid to say any of this, and I have no particular liking towards them at all.
