I’m genuinely curious how this happens. I remember my first job in the industry, just out of university. I knew nothing about security, but still wouldn’t have done that. My first gig was in a credit union software company, and the security standards were nonexistent, yet we still had more reasonable passwords than this (which sounds like an installation default).
I'll tell you how this happens: Colleague #1: "What password shall we set?" Colleague #2: "Just leave it default for now as we're still testing, we will change it later".
You would be shocked at how nonchalant and downright negligent people can be about security at even the largest companies in the US. I did consulting work at a large insurance company that had the contact information, ssn, and PHI of pretty much everyone in the America (and I mean everyone). I lost track of the number of times people checked in the production password into git. In fact our production cassandra instance still was using the default cert password 'changeit' when I left. Unsurprisingly, this company was filled with contract workers and H1B workers that were barely able (if at all) to get their work done.