Why do papers published by people in tech industry often have such a large number of authors?
TL;DR: results in industrial practice are often much more of a product of team work, rather than the &quot;every student works on their own thesis&quot; model that we usually have in academia. This is also reflected in the length of author lists.

The work mode of an industry lab (or, even worse, of a group of day-to-dat software engineers in industry who just happened to become involved with a paper) is typically different to your average academic lab. To wit:
Academic project (simplified, of course):
Somebody (a PI, the student themselves, or somebody in between) has an idea for a research paper. A person (often, but not necessarily, a student) takes responsibility for executing it, and collaborates with their advisor and, maybe, one or two other students on executing it. Importantly, for this &quot;driver&quot; of the project it is usually of high importance (because it goes into their thesis in the case of a student), and they invest a significant portion of their time on it. The other collaborators usually only invest time in specific roles (giving feedback, doing specific analyses, helping with paper writing, etc.). In short, there is often one person responsible for bringing the project all the way.
Industrial project (particularly in the case when a software company is reporting on aspects of their practice, as in many of your examples):
Somebody (often a member of the research division of the company, sometimes an academia-affine practitioner) has an idea for a paper. They start working on it, but they cannot commit more than a fraction of their time on it (because even for industrial researchers, writing papers is often much less a core focus of their job profile than for students or academic staff), so they gather collaborators, who likewise cannot put more than a few hours here and there on the project. Additionally, for such &quot;report of a practice&quot; kind of papers, many people have typically contributed to establishing the practice, and it is bad tone to leave out key players (unless they don't want to contribute to the paper). In short, while there may be a coordinating person as well, nobody really has the time to work on this paper full-time, and many people have somehow contributed to the work being reported on, so automatically the author list swells.