Having lived through the transition from “using expensive commercial tools that run on expensive commercial UNIX” to “using expensive commercial tools that run

Having lived through the transition from “using expensive commercial tools that run on expensive commercial UNIX” to “using expensive commercial tools that run on RHEL” I think I can tell you exactly why Debian was not chosen as the successor to expensive commercial UNIX. First of all, the general transition to Linux was started by engineers, customers of UNIX, who were tinkering with Linux. We weren’t software engineers and not super interested in how Linux worked, just what we could do with it. Debian was a chore to install, in the way of getting things done. Red Hat, on the other hand, was easy to install. Red Hat was the distro of choice for experimenting with Linux. The other side of it, the business side, is that RHEL met the need of, “see boss, this is fully supported, just like UNIX.” That had to be a thing before these types of businesses would transition from UNIX to Linux. Only after that transition would front-line engineers be brave enough to sneak a RHEL clone like Centos into the mix. Sadly, Debian just didn’t stand a chance in this situation. Fast forward to today and now you see front-line engineers hacking Ubuntu LTS distros to look enough like RHEL for the commercial tools to run on it. You still have to keep a RHEL box around to reproduce issues before going to support with issues in the commercial tools, but that’s much cheaper than a whole fleet of RHEL boxes.