[bureado]

RPM-based distros certainly led server OEM shipments back in the day, but that didn't mean Debian wasn't being used extensively in the backoffice.

As others have pointed out, APT played a critical role in Debian's popularity as open source software grew and early naive software distribution methods were outpaced by complexity.

I won't weigh in on Canonical's broader presence across verticals, technologies, etc., but Ubuntu is widely recognized as the most popular Linux in cloud platforms. I believe this is a direct result of APT coupled with a more rapid release pace.

RPM-based distros remain extremely valuable and extremely popular in many scenarios, particularly when someone has to run a product from a proprietary ISV or something that has a very complicated certification model.

In some cases, but certainly not all and in my opinion in a decreasing amount, the choice of distro might be tied to how active a particular company is in the upstream kernel. "Buy Red Hat because they contribute to the kernel". Suffice to say as decision makers perceive that their app isn't the kernel, that decision criteria is shifting (thankfully, many RPM-based vendors including Red Hat have many other value items to add)